Show My Caller ID - Spinning Wheel

Until now I have never had an issue with this feature. Reviewing the conversations others have had on these forums, it seems this issue rears it's nasty little head from time to time. Essentially, I would like to prevent my caller id from displaying when making official calls with my personal phone. This used to be possible by disabling the Show My Caller ID setting in Settings > Phone > Show My Caller ID. Now the spinning wheel is proudly displayed continuously.

The phone has been restarted and backed-up and restored following the instructions in the previous conversations all to no avail. The same issue affects an iPhone6s and iPhone7 both of which are running the latest iOS version14.6.

How can I get this feature re-enabled?