Did the installer went to check the outside cable from junction box pole? My case was similar, previously I saw the cable outside was a bit damaged from being in the middle of coconut leaves and also too much sag. So suggest to them to check maybe there were damage outside.

Turned out it was, there was a damage to the cable like someone trying to cut it off. They reinstall new wire direct from the pole to my house, foc since damage was outside.