DIGI 1A modem with hyperaccess

Hello,
I have a terminal monitoring equipment in the field the units call in and the modems are supposed to answer.
I have one DIGI 1A modem and it will call out ok but if something calls in it picks up and hangs up 3 seconds later, this modem used to work,

I am running XP
Hypperaccess 8.4 and using a DIGI 8 port seriel card

Thanks for all your help.

PS. anyone know of a good source for someone not used to communication for working with this type of thing. I want to learn.

I solved the problem