It won't let me send pictures through text message on my iPhone 4?

It used to let me send pictures through texts on my iPhone 4, but now when I try it it just keeps saying 'failed' with the red! Next to it. I have tried even when my phone has had Internet but still no luck:/ What else can I do to send the message? And I do have enough credit btw

I think with most Phone providers they charge texting and picture messaging separate. Maybe the plan you got limits your picture messaging. You could call them and they could tell you all about your plan and maybe help with your phone.