Problem with UBOSS telephone service

[Terryphi]

A number of people have reported intermittent disconnection from the UBOSS telephone service. This leaves users unable to make or receive calls. I found that rebooting the router resumes connection but it does not last. Customer service are investigating.

[Simon]

I don't really use mine all that much to notice any outages, but I did have an issue where a caller tried repeatedly to call but received a message that the line was busy.  It wasn't and my phone never rang.  This was over a period of about four hours.  I reported the incident to Support but they said they couldn't investigate as the problem had since resolved.