Order a free SIM Activate your 48 SIM
You seem to be using an iPhone?
If that's the case then it's almost certainly this issue due to the stupid way that Apple do things which causes problems for many, many iPhone users while roaming abroad on some networks (including 48):
iPhone abroad issue
You may need to try that many times before it works.
It may help to toggle airplane mode on and then off and then quickly try to "catch" the local network so that you can change the roaming profile as explained above.
Hope this helps.
Did that help at all?