If you have lost your LINE chat history after transferring phones, recovery is dependent on your backup configuration.
If you have previously backed up your chats to iCloud (iOS) or Google Drive (Android), you can retrieve them after account transfer.
Make sure you're signed in with the same Apple ID or Google account, and that iCloud Drive or Google Drive has enough storage.
During the LINE setup on your new device, you will be asked to restore your conversation history.
If you didn't back up but had set a backup PIN on your old device, you can still recover the last 14 days of conversation history, even if you move OS.
Unfortunately, without a backup or a backup PIN, your conversation history cannot be recovered.
This is the information we have, but if you have more insights from your experience, please share in the comments.
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