In Applications, check if Travis CI is added in:
Deny Travis CI access from Organization > Account settings > Third-party access:
In Account settings, check if Travis CI is added in:
- Installed GitHub Apps
Delete .travis.yml from your repository root.
Uncheck Travis CI status checks from your repository Settings > Branches > Branch protection rules:
- Travis CI — Branch
- Travis CI — Pull Request
Don’t forget to save your changes.
Delete Travis CI from your repository Settings > Webhooks:
Finally, don’t forget to change your plan to the free one so you stop paying.