Your issue seems to be caused by an unreachable URL that returned a 5xx server error. Please verify the URL in your Cloud Scheduler job is correct, accessible online (if it’s public), and that the server it points to is working properly.
Also consider re-enabling the Cloud Scheduler API, redeploying your Cloud Function, and resuming your Cloud Scheduler job.
I have the same issue… a scheduled job has been running successfully for ages and I made a minor change not affecting the url and now it fails every time with the unreachable url error. A similar function that I havent edited is still working
For me problem seemed to be in the function itself. I have 2 cloud scheduler jobs running and I had to fix my functions, test them and try running again. Basically, I had some errors in my functions. Make sure to test you functions in cloud functions.
As @mokhinurra1 suggests above, check your function for errors. I think the URL_UNREACHABLE error is misleading, when I looked at the execution logs for my function I actually found issues with the code. When I fixed those, the scheduled job ran as expected
For me it was my query to firestore that needed an index, you can check logs in your cloud function UI interface, your scheduled fun, settings, view logs
For me it was an issue in my scheduled firestore query, missing an index.
You can check the logs of your scheduled function in you function list UI, your function, settings, view logs