You said you have a data plan, but to be clear, you must have a blackberry data plan -- a blackberry specific data plan -- to use the native blackberry data appliations. Sounds like you don't. That could be the explanation of why you only have wap data.
And if you have purchased a blackberry data plan and still do not have blackberry data service, then make sure the service books have been pushed to your blackberry handset. See How do I resend my service books? - BlackBerryFAQ
If after all that, you still don't have blackberry data service, and you know you have adequate signal strength at your location, try the hard reset already suggested.
After that, if still no joy, I think it would be time to call the carrier's customer service.