Best mobile phone network for Newcastle?

Visited newcastle uni and I couldn't get much signal in buildings. Thinking my phone network may not have the best coverage for the area.

Does anyone have any suggestions for the best mobile phone network for the area?

I use three, how old is your phone?
https://www.signalchecker.co.uk/newcastle-upon-tyne

Only about 5 yrs old.

I'm using lycamobile, according to the signal checker it should have good coverage but it definitely doesnt.