This isn't an iPhone by any chance?
I suspect not as you seem to be posting from a Sony?
If it is an iPhone then see here but adjust for 48:
If it's not an iPhone then try powering off, taking the SIM out, gently cleaning the SIM contacts, reinserting the SIM, powering on and doing a manual scan for networks. If you see 48 (or O2 or Three?) then try to manually connect.
Make sure that data roaming is still enabled.
If that still doesn't work then you may need to contact 48 support for more advice:
Hope this helps.
Did that help at all?
What exactly did you try?
Did you contact 48 support as I suggested?
Did you get this sorted?
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