``I thought I sent a message on LINE, but the arrow mark never disappears.'' ``Even though the unread badge is displayed, the message doesn't appear when I open the chat.'' Have you ever experienced something like this?

As of February 2026, LINE message sending/receiving problems are frequently reported on SNS. In this article, we will organize the reasons why you cannot send or receive messages on LINE into 8 reasons, and provide easy-to-understand explanations of how to deal with them for iPhone and Android.

First of all, this! Basic check that can be done in 3 seconds

Before getting into the solutions, first check the following three things. This is often enough to fix it.

  • Turning airplane mode on/off: Turn airplane mode on from settings, wait 5 seconds, and turn it back off. Communication may be reset and restored
  • Restart the LINE app: Close the app completely (task kill it) and reopen it
  • Restart your smartphone: Press and hold the power button → Restart. It's simple but highly effective

If this does not resolve the issue, please check the following solutions for each cause in order.

Cause 1: Unstable communication environment (Wi-Fi/mobile line)

According to LINE Official Help, the most common cause of problems sending and receiving messages is Communication environment problems.

This problem is particularly likely to occur in the following situations.

  • Places where signal reception is difficult, such as subways and elevators
  • Connected to free Wi-Fi, but actually stuck at the authentication screen
  • Mobile data communication restrictions (speed restrictions) are applied at the end of the month

Workaround:

  1. Turn off Wi-Fi and mobile data and turn it back on after 5 seconds
  2. If you are connected to Wi-Fi, turn off Wi-Fi and try using a mobile network (4G/5G)
  3. If communication is restricted, purchase additional data or move to a Wi-Fi environment

Roughly speaking, the fastest solution is to "switch the line".

Cause 2: The LINE app version is outdated

If the LINE app is not the latest version, you may experience problems sending and receiving messages. LINE Official Help also recommends updating as a workaround.

Workaround:

  • iPhone: App Store → Search for “LINE” → If the “Update” button is displayed, tap it
  • Android: Google Play Store → Search for “LINE” → If the “Update” button is displayed, tap it

Be careful if you have automatic updates turned off. LINE is an app that requires regular updates, so we recommend turning on automatic updates.

Cause 3: The other party is set to "reject message reception"

If you send a message and the recipient doesn't receive it, the recipient may have turned on Do Not Receive Messages.

This is a feature that allows you to "not receive messages from anyone other than your friends" in your LINE settings. This means thatif you aren't on their friend list, you won't receive the message.

Workaround:

  • Ask the other person to add you as a friend (via QR code or ID search)
  • Communicate through other methods such as group talk

By the way, there are cases where your "reject message reception" option is turned on and you are unable to receive messages from people you don't know. You can check from LINE app → Settings (⚙️) → Privacy management → "Reject message reception".

Cause 4: Failure on the LINE server side

Even if there are no problems with your environment, you may be unable to send or receive messages due to a LINE server failure. In February 2026, there were multiple reports that ``LINE suddenly became unable to send'' and ``unable to receive'' on X.

How to check if there is a problem:

  1. Search for "LINE failure" on X (Twitter) and check if there are any reports of the same symptoms
  2. Check the LINE outage map with Downdetector
  3. Check the official announcement on LINE Official X Account (@LINEjp_official)

In case of server failure, there is nothing you can do. You have no choice but to wait for recovery, so don't rush, wait about 30 minutes to an hour and try again.

Cause 5: Notifications are not received/badges are not displayed (you do not notice that they have arrived)

There are many cases where the message actually arrives, but you don't notice it because you don't receive a notification.

For iPhone:

  1. Open "Settings" → "Notifications" → "LINE"
  2. Make sure "Allow notifications" is turned on
  3. Check if "Badge", "Sound", and "Banner" are all turned on
  4. Check if "Notification delivery method" is set to "Immediate delivery" (if "Timed summary" is used, notifications will be grouped together)

For Android:

  1. Open "Settings" → "Apps" → "LINE" → "Notifications"
  2. Make sure "Show notifications" is turned on
  3. Check if individual items such as "Message Notification" are turned off
  4. If Battery saving mode is on, notifications may be restricted, so set LINE as an excluded app for power saving

Cause 6: LINE does not work properly due to insufficient storage

If your smartphone has extremely low free space, the LINE app may not work properly. Not only can it cause messages to be sent and received, but it can also cause the app to freeze or force close.

Workaround:

  • iPhone: Check the free space in "Settings" → "General" → "iPhone Storage". Organize unnecessary apps and photos
  • Android: Check the free space in "Settings" → "Storage". Delete cache and organize unnecessary files

As a guideline, we recommend that you have at least 1GB or more of free space.

Cause 7: LINE account has been suspended

If you can't send messages to anyone, LINE Official Help says that usage suspension measures may have been taken.

The following acts constitute a violation of the Terms of Use.

  • Spamming (sending mass messages, promotional communications, etc.)
  • Posting inappropriate content
  • Create multiple accounts

If your service is suspended, an error message such as "Authentication is temporarily restricted" will be displayed when you start LINE or send a message. If it is a temporary suspension, it will be automatically restored after the period ends, but if it is a permanent suspension, you will have no choice but to create a new account.

Cause 8: The other party has changed or deleted their account

There are also cases where LINE account transfer fails when changing devices and the other party creates a new account.

In this case, messages sent to the old account will not be delivered. The message appears to have been sent, but the recipient is no longer using the account.

How to check:

  • The other person's profile picture or status message hasn't changed for a long time
  • Reads don't last forever
  • Confirm with the other person using other means of contact (phone, email, etc.)

Last resort if the problem persists

If the problem persists even after trying all the solutions above, please try the following.

  1. Delete LINE cache: LINE app → Settings (⚙️) → "Talk" → "Delete data" → Delete "cache data" (talk history will not be deleted)
  2. Reinstalling the LINE app: ⚠️Be sure to back up your chat history beforehand. LINE app → Settings → Take a backup with "Talk backup" and then delete the app → Reinstall → Login
  3. Contact LINE official: Report the situation from LINE Help Center inquiry form

Reinstalling runs the risk of erasing your chat history, so be sure to make a backup first. Please never forget this.

FAQ

Why does an arrow mark appear next to messages on LINE and does not disappear?

An arrow mark (↑ or 🔄) is a sign that the transmission has not been completed. Displayed when the communication environment is unstable. The problem is often resolved by switching between Wi-Fi and mobile data, or restarting the smartphone.

What should I do if LINE shows "Unable to send message"?

First, check your communication environment and try sending messages to other friends. If you cannot send it to anyone, you may be suspended from using LINE. If you are unable to send to a specific recipient, it may be due to the recipient's "reject message reception" settings or account changes.

Why is the unread badge on LINE displayed, but when I open the chat, there is no message?

This is caused by a cache problem in the LINE app or a temporary server failure. Most of the time, the issue is resolved by restarting the app or deleting the cache. If the problem still persists, try reinstalling the app (backup required).

Where can I check LINE failure information?

You can check on the LINE official X account (@LINEjp_official) or Downdetector. It is also effective to search for "LINE failure" on X and check if there are any similar reports during the same time period.

References