Error Message When trying to activate Facetime/iMessage

Hi Guys

everytime i try to activate iMessage Or Facetime i get the following message

Sorry your text messaging service is currently unavailable due to insufficient funds.Please top up your phone and try again.



right so i cant even call my Carrier (T-Mobile) because when i try to call them it costs 25p to get through to them :eek::mad:

Things i tried :

Took off sim card
tried without sim card
turned off phone


I Have an iPhone 4S if that helps


FROM : The UK


thanks in advance



quick question :

can you use facetime / iMessage without the internet