Hi there @RDJ79 welcome to 3Community.
I'd love to help you with this, I'll need to get a little more info so I know where to start. Do you know what plan you are on? Since you topped up by €25 are you on Three Connect Complete? If you are this is a draw-down plan, meaning you top up by €25 and this €25 is deducted to activate your plan. Are you able to use calls, text or data on your phone or are you getting an error?