iPad won't connect to anything other than 3G

[NetworkNorm]

Hi,

I have a 5G SIM in my ipad and have been happily using 5G (when available) with no problem.. However since about a month ago, my device won't connect to anything other than 3G.

I've checked and double checked all of the settings to make sure everything is set to use 5G and all appears in order. Looking at my O2 account, it correctly shows I have the 5G bolt-on.

Am really confused as to what could be causing this? And yes, I'm definitely in an area with good 5G coverage, my iPhone (also with O2) connects with no problem. 

[MI5]

@NetworkNorm 

What do you get with your phone sim in the iPad?

Guide: How can I sort out my network issues? 

https://www.o2.co.uk/apps/my-network

[jonsie]

What is the APN setting?

[NetworkNorm]

Put my work SIM in, as my personal o2 phone is eSIM, and iPad happily connected to 4G. Put my o2 SIM back in and stuck on 3G. 

APN settings are:

mobile.o2.co.uk

Username: o2web

[jonsie]

Try changing to idata.o2.co.uk

[MI5]

@NetworkNorm 

I'd pop in store with photo ID for a new sim.