As part of troubleshooting you may need to revoke the access and re-integrate with your git integration to verify the issue is related to the git service webhook being used. You can revoke the access by following the below steps:
Click on the avatar on the left main menu > Personal settings
Then, > Git Integrations > Revoke Access for your git provider account that has the issue.
Once, you revoke the access, you can go ahead and integrate with your git provider again as noted in the documentation here: https://ionic.io/docs/appflow/quickstart/connect