Failed to send on text message?

I bought a couple of little TracFone NOKIA 1100's for my friend and I, and at first we enjoyed text messaging each other, but now when she tries to send a text message to my phone, it says that it failed to send.

She still receives my text messages with no problem.

I wonder why it's doing that when it worked perfectly earlier?

could she have run out of credit? perhaps all she has is the free local
calls remaining
"Shaman683" <Shaman683.1uek1y@nospam.cellphoneforums.net> wrote in message
news:Shaman683.1uek1y@nospam.cellphoneforums.net.. .
>
> I bought a couple of little TracFone NOKIA 1100's for my friend and I,
> and at first we enjoyed text messaging each other, but now when she
> tries to send a text message to my phone, it says that it failed to
> send.
>
> She still receives my text messages with no problem.
>
> I wonder why it's doing that when it worked perfectly earlier?
>
>
> --
> Shaman683
> ------------------------------------------------------------------------
> Cell Phone Forums: http://cellphoneforums.net
> View this thread: http://cellphoneforums.net/t186643.html
>

Thank you for your reply. No she has at least 70 min in her TracFone right now.

Could a full "Sent" mailbox be the problem I wonder?