No Ranging Response Received - T3 time-out

Hello, I have been getting intermittent connection issues for past few months, the connection would drop and back online in few minutes or up to an hour in some cases. This consistenly happens at least once in the evening. I use Surfboard Model SB6120 and the modem log shows "No Ranging Response Received - T3 time-out", at the time when the issue happens. 

I see other threads that there is some issue with the uplink and requires tech visit. Can you advice how this could could be fixed?