While calls were happening, the system stopped calling. The error message was "There is a time synchronization problem with your system, please tell your system administrator".
It could be a number of errors, but according to our provider, it was because our RAM wasn't working anymore. The server was 2 years old and was used every weekday since then.
When I replaced the RAM, it was working again for a while. But then the problem came back.
Until now, I still don't know why the error happens and I haven't been able to get back to it.
