Same BP got the previous one I spent 6 months chasing BP, they lied to Motability numerous times, told me one thing motability another. Even the complaints guy I was dealing with lost it with them. In the end they paid for me to have my choice fitted.
Have you had the DNO check or change your cut out fuse to 100A as that needs doing, meter tails need checking and or replacing too. Between cut out and meter is the DNO between output of the meter and your fusebox is yours.
I had UKPN out 3 times as I had a looped line so had to be unlooped then the fuse replaced with actually increased the voltage by 5 volts
Good luck and do fill in the oibe complaint form with motability as the people on the end of that actually know what they’re doing unlike the rest imho