So you have created backups of Line chats on your Android phone. Now, you want to restore those chats on a new device or on a fresh installation of Line app. If you have created your Line chat backups using the Backup All option, then it can be imported using the steps shown in this guide.
If you want to restore your chats on a new Android device, you will need to log into Line on your new device using your registered email address. Before you import the chat history, make sure that the backup file is stored on a SD card. (The backup file is named something like LINE_Android-backup-chat-dhjhfvjhgyvj.zip.)
Steps to import chat history in Line App on Android
Tap on Chats in the top Menu then Tap on the name of the contact whose chat history you want to import.
Tap on the V like icon at the top-right.
Tap on Chat Settings.
Tap on Import Chat History.
Tap on Yes.
If you see the message as shown below, your chat history has been successfully imported.