NEC sl 1000 incoming call issue

[zero5]

Hi all,

At a costumer there is weird issue.
These are 2 separate companies with the Nec sl 1000 in the main building, both have separate receptionist(ext 10 in main building and ext 15 in secondary building with each of them having 2 trunks for each building)
The receptionist (ext 15)of the secondary building , said that during the week the phone started to ring only 2 times then it closes, but now they don’t receive any calls, but the can make internal and outgoing calls.
When I called her from ext 10 from the main building she sees the ext 10 calling and hears a beeping sound on her phone.
The ext 10 of the main building is working normally no issues
I checked all the lines with an analog phone and both lines can receive and make calls.
Also switch the phones but still same issue, rebooted pbx, but still nothing.
Also their inmail isn’t working, because the calls aren’t reaching ext 15
I looked through the extension and the configuration is the same and don’t see anything that changed.

Everything was working perfectly then suddenly this issue appears
Does anybody have an idea?

Thank you in advance

 

[Ragnorak]

This is difficult to diagnose without more information about how the lines are programmed.

You could check Program 93-01 and see what Night Mode they are in (there are 8 of them.) The default service code on the SL1100 for changing night modes is 718 and if someone accidently tried to dial a 718 area code or exchange from the intercom that might have resulted in the mode changing. If the lines are not programmed to ring the phones in all 8 modes that would account for the lack of inbound calls. The calls being sent to voicemail is also something that is mode dependent so that would explain why the calls are not reaching extension 15's voicemail too.