WeChat restricted my login after I changed my phone, how can I access my chats again?

If WeChat restricted your login after you changed your phone, first attempt the standard recovery route: on the login screen tap “Unable to Log In?”, then follow the prompts to verify the phone number or email linked to your account.

Once you regain access, restore your chats by using the in-app migration or backup feature: on your old phone go to Me > Settings > Chat / Backup & Migrate Chats (Android) or Me > Settings > General > Chat Log Migration (iOS), then on the new phone select Migrate Chats to Another Device.

This is the information we have, but if you have more insights from your experience, please share in the comments.