Saturday
Saturday - last edited Saturday
Is "SIM unavailable" the verbatim error message?
What make and model of phone is it?
Was there any recent software update or settings changes?
If it says "SIM unavailable" then I presume that nothing is working?
Connection to the 48 network - i.e. signal bars, incoming/outgoing calls/texts, mobile data?
Try reseating your SIM in case it has become dislodged?
Can you try your SIM in another unlocked phone with the APN settings configured correctly to see if it works there?
Maybe try a replacement SIM if you can't get it working again?
If you need to contact 48 support about this then see the links in my signature below.