Did it ever work or have you just joined 48?
Is the SIM activated/registered?
Have you tried switching off, reseating the SIM and switching on again?
What is the exact error message?
Is your phone unlocked for use on any network?
What sort of phone are you using (make and model)?
Hope this helps.
If the error is "your sim is permanently disabled" then it sounds like you or somebody else tried to enter the PUK too many times?
This FAQ topic explains how to get a new SIM:
All you need to know about SIMs
Hope this helps.
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