Hi HTCTOUCHPUNE- welcome to 4WM
This is a very unusual problem, but one that we have seen a few times in the past. Your experiments confirm that both your Touch, and your SIM card are capable of working independently, but not together.
This suggests that your network is having a problem with the combination of SIM card ID code and device IMEI number.
The only cure, as far as I know, is to request a new SIM card from your operator, or try to get your existing one re-registered on your account.