Oddly like mentioned on Mac Power Users sometimes my iOS 13 iPhone X has full signal on 4G but cannot do anything with data. However oddly I seem to find this in one spot in town! So I am not sure if it’s the phone or some lead in the coffee shop.
@adamprocter That's normally because the tower is oversubscribed. Yes, you've got a strong signal but there are too many connections. The number of times I have to turn off 4G in London, despite having "full" signal is ridiculous.
@colinwalker yes of course makes sense I have not had this problem before however winchester has a very popular Christmas market so to be fair it is a lot busier in town now...