You'll need to post more info if you want assistance from the Community Forum.
Was everything working OK before or are you just getting started with 48?
If the latter then you should review the Getting Started FAQs in case they help:
Did you successfully activate your SIM?
Is your phone unlocked for use on any network?
What make and model of phone is it?
Are there any error messages shown on screen when the 48 SIM is installed?
Do you have a connection to the 48 network - i.e. signal bars?
If not then if you do a manual search for networks can you see and connect to 48?
Can you receive calls, send/receive texts, use mobile data?
If you need to contact 48 support then see the links in my signature below.
