Hi petebrown71,
Welcome to our community forums!
I'm sorry to hear you're having some problems with your new sim card.
Would you be kind enough to tell us a bit more about the problems you're experiencing? Is it on all incoming and outgoing calls? Is it only happening sometimes? Any specific networks?
If you haven't already I would recommend performing a manual network search to see if that makes any difference. It is also worth trying your sim in another handset if you have the means to do that.
Look forward to hearing from you,
Hetty_R