"An issue with your internet - schedule a free technician visit"

For months I received texts and emails warning me that you've "identified an issue that may affect your internet and video services".  After finding no way to stop these messages, we agreed to have an on-site technician inspect our lines and service.  

First, the technician had NO idea why he was there... his orders only said that we called for service (not true).  Dispatch also had no reasons for the service visit.  So, we showed him the texts and emails we've been given, so he did a deep inspection -- he checked the cables and connections that lead to the house and found no problems or degradation.  He inspected the in-house cables, and same results -- no degradations or drops.  Everything about our LAN and WAN set up was clean and without issues.

Even so, the messages continued.  Eventually (which took many days) we reached someone by voice who indicated that there were no notes or flags on our account or service, and therefore it was impossible to determine what issues have been identified.  Somehow, they managed to stop these messages.

Now they have started again.  Please assist me in ending them, OR (preferred for a technician myself) give me actual measurable issues you have observed, or service issues that are being captured.  Over the course of a year, no one has been able to do that, nor has an on-site technician been able to find any issues.  We certainly do not feel comfortable allowing a technician inside our home for unspecified and undocumented reasons.  If issues cannot be quantified, then clearly the solution is to either do more to identify those problems or wait for it to actually fail.