Pixel 5 user here so know my phone isn't 100% compatible, however I experience connectivity issues whenever my phone falls back from 4G to 3G/H+ and I get the exclamation mark on the signal icon.

I noticed this happening over Xmas at my family house where 4G wasn't as strong. But also happens in the middle of Wellington where I live.
I usually fix by triggering airplane mode on and off.