Maybe GitHub showed you a warning (as you can see on the warning below) on one of your scheduled GitHub actions.
If so, let's consider implementing a Keep-Alive strategy.
Take a look at the keepalive.yml action. This scheduled action runs at 00:42 UTC on the 1st of every month.
A .keepalive file is added with the current date-time (human-readable) at the repository root and commits it.
Feel free to report any issues, and make pull requests to improve this GitHub action.