On that particular time, it was raining outside, and when I touched the earth wire, it felt quite unpleasant. Touching it now for example, I do no feel anything. I.m taking about the yellow/green continuation as a single wire of the star ground point.
I can't see a problem if you could drive an earth rod (copper) into the ground external to the property and connect that to the earth coming into the building.
https://www.tlc-direct.co.uk/Product...xoCHl0QAvD_BwE.

Glad to hear you have finally got it working.