If you've changed to a new mobile phone, you can transfer chat history from your old mobile phone to your new device as the following method:

Log in to your WeChat on your original mobile phone, tap Me > Settings > Chats > Backup & Migrate Chats > Migrate Chats to Another Device > Select Chat History, and then you can transfer the chat history through the following three ways:

1. Check the boxes next to the chats which you want to migrate to your new phone.

2. Tap Select all at the bottom of the screen to choose all the chat history.

3. Tap Select Time and Content to select the certain date and content of your chat history and then follow the instructions and operate on your new device.