Hello. Thanks for the replies. Yes I tried the servic checker and I also spoke to a specialist in the phone. It says good inside and outside coverage for 4g. I have full signal indoors.
I tried in a different town yesterday. Only 2mbps and kept cutting out with a little x next to the 4g symbol. Same in both pixels.
Strange it's gets faster speeds swapped into the iPhone and even does one fast speed test in the pixel immediately after swapping back into it, then goes slow again.
I was fine on BT (EE) with the same phone.
If I go to setting and set preferred network to 3G, it's actually much faster