Actually I am house bound at the moment so it only happens at home. But I have spent 2 weeks on another location last year and it never happened once.
The single is terrible once I am at home. When family and friends call I have to put my phone near a window and on loud speaker so my phone is not moving. But even this works all the time.
WiFi calling was working on my old phone samsung a71 so it should d already be active. But it just doesn't work on my Samsung note 10plus.
I forgot to add that I have a Samsung tablet which I operate on the same EE network (for data) and it does not happen to that service at all.
I am disabled and recovering from a life saving operation so I can really afford to be with my mobile.