Just got myself a new T-mobile PAYG SIM-card. I am currently abroad and when I switch on my mobile phone, it wont access any network. Called T-mobile and they said my card is available for roaming and I should just "keep rebooting the phone". I asked if I shouldn't have made a call in the UK first, but the lady said "she didn't think so". She was not very knowledgeable though. Should I just wait 24 hours or will roaming only work after making a call in the UK first? Thanks