Trying to send an MMS from iPhone 5 AT&T to T-Mobile Help

[mac.fanatic]

I am trying to send a friend on the T-Mobile network pictures from my iPhone 5 (I am on AT&T). On my side, they are sending but he is not receiving them. He, however, can send me pictures and I will receive them. What can be the issue here and how can we solve it?

He has tried a restore on his phone and a new SIM card. He is using a smartphone as well, but not the iPhone.

 

[Applejuiced]

Nothing you can do on your end.
Its a network issue with either network not communicating with each other right.
Sometimes I dont get verizon texts or mms on my AT&T phone at all or other times they come 7-8 hours later.