In normal circumstances, data between GTasks and Google Tasks are kept in sync with each other. If your tasks are not syncing, please follow the steps below to troubleshoot:

1. Make sure your network is available and stable enough for data syncing
2. Allow GTasks to read Google account on your phone and authorize GTasks with Manager your tasks
3. Check whether you are logged in with the same account on Google Tasks
4. Authorize Google tasks on manual with Google OAuth 2.0 on Add Account screen

Contact us through email if none of the above works for you.