Why did DISA stop working?

Question

Telephony

Automatic telephone exchange - Panasonic KX-HTS824

We have three subscribers:
1. Group "Accounting" - 3 devices,
2. Domostroy
3. Engineer

Incoming calls are received in the analog port CO1.
CO1 is set to dial DISA 501, which reads the recorded message (Press 1, 2, 3...etc) during which, by pressing a code number, the caller will be taken to the appropriate party. Everything worked perfectly. Two weeks later, a problem arose: DISA plays the message to the caller, but does not respond to the entered code for forwarding to the desired subscriber.

If you configure the CO1 port to call a specific internal group or subscriber, then everything works.

*Solved
By advice from other forums.
While listening to the CO1 line after the gateway, but in front of the station, no dialing signals were heard. After initialization to 0, the PBX itself set up DISA and, upon re-checking, it worked as it should. Having done all of the above, at the end I noticed that the switch, which is connected in front of the gateways, judging by the feverish diodes, has torn ports. The problem turned out to be his own inattention. Thank you all for your attention! The question is closed.

Answer 1

Stupidly: reset to factory settings and fill in the same program again, or reprogram manually after reset.
Didn't work? Question for warranty service.