Did you activate your SIM and is it installed in your phone and getting a signal ok?
What does it say on your My48 account?
https://48.ie/my48
Does it indicate that you have 1GB of free data?
If so did you configure your internet/APN settings?
https://community.48.ie/t5/The-Knowledgebase/My-Internet-is-not-working/ta-p/45928
If none of that helps then you may need to contact 48 support.
See the link in my signature below.
Hope this helps.
