Poor mobile service in my area

[skyqkid]

iPhone 11, latest apple software v17.6.1

Increasingly finding mobile service for 4G in areas nearby to be poor or no service although it shows 4G service as being active on my screen or sometimes E.

Even restarting the phone does not help.

My wifes XR iPhone again with v17.6.1 software has the same issue in the same areas.

The coverage checker shows full coverage and no issues in nearby areas with service etc.

I'm at the stage of looking to change provider, but my contract early leaving would cost so much

[twilight+princess]

Same for me. Checked for problems but there's none in my area. 
4G coverage shows 3-4 bars but no or slow internet.

I'm considering going back to 3 at the end of my contract.