Connectivity issues

I got a O2 sim when I bought my iPad and it worked fine. Then I got a Three pre-paid sim as it's cheaper than O2 and it worked great. When the data ran out I got another Three sim off Amazon but all I get is No Service. I phoned Apple Care and they happy that there's nothing wrong with my iPad. So I phone Three and they are happy that the sim is activated but still No Service.
After sending the sim back to the seller And getting a new sim (Three) I've got the same issue... No Service.

This is what I get trying to activate the sim.
Attachment 13587

Attachment 13586

Any advice?

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