troubleshooting Rowe ami 100. 1994 model

My grandmother has a Rowe ami laserstar 100cd from 1993.

When I turn It on it runs it's diagnosis and then it says serial 00001205. I then flip the switch inside for program mode and it says. Error exists. None of my button are working on the outside which my manual has told me to hold reset and press other buttons. But nothing happens. I was able to turn it off and get free to pop up and before u can really do anything it makes two little clicking sounds before it goes back to reading serial 00001205. Anyway it would mean a lot to get to work for the family and I have told u everything I've done so far I would also like to mention that I pressed any and every rest button checked all my wire and connections and everything is in great shape thx