How to escalate support issues.

I have an issue with Microsoft's Backup and Restore and File History on Windows 11.   Specifically, the shadow copy space is empty and set to 1GB, but the error complains that the shadow space is full or too small.  (I've run through every support article available)    This was all working fine (on Win 11) until a couple of weeks ago.

However, the support chat claims this is 3rd-party software and that Windows 7 backups cannot be restored to Windows 11, which has nothing to do with the issue at hand.   The machine has never had Windows 7 installed, but the support agent insists that Windows 7 is unsupported, and hence, I'm using 3rd-party software and will not transfer me to anyone else, and no longer responds.

The agent's reasoning just doesn't make sense to me.

Is there any way to raise a support issue for Windows 11 or its components?

This reminds me of trying to install Windows Vista; although it was a forced upgrade that failed, the support agent just insisted Microsoft Vista wasn't Microsoft software.