My Bro has a BoostMobile Blackberry 9330

Ok here is the deal, he has Boost Mobile Blackberry 9330.

Anyone can send him an mms & sms AT&T, Boost, Sprint, Verizon all can send me text messages.

but for some reason, only tmobile customers cannot send me a text.

Not 1 or 2 people, i have 15 people i know with tmobile, and when they send a text they get the following message,

Free MSG: Receiver HisMobileNumber unable to receive message -
Message Blocking is active

and that is from every tmobile customer.

He has reset his phone, completely erased and reinstalled software, and still nothing.

he contacted boost and they have no text blocking active on his account.

he has refreshed his service books and provisioned my phone and still no good.

I contacted tmobile customer service and they said there is nothing on my end for that should be blocking text blocking either.

But it is not only me it is all Tmobile customer cannot send me SMS or MMS

does anyone have this problem or know somone with this problem. and know how to fix it?

let me know please

Thank you