DVLA V5C address refusal, unable to tax vehicle

Mickwick

Currently living transiently in a converted van and pay for a residential, street address for post. Address is accepted by everyone except for V5C vehicle registration as DVLA claim they "can't" register to a mail drop address as we're not easily contactable, yet they keep writing to us there and we respond.

Gov.uk says new V5C was issued Oct 2021 when we first tried to change address but in reality it has been frozen. As a result we are unable to tax, sorn, transfer ownership or change the address for our vehicles. With some back and forth drivers licences have been issued to our postal address ironically.

We are currently in dispute with DVLA about the address and no, we don't have a friend or relative that would be as reliable as the service we pay for (it is not a p.o. box) but wondered if anyone has any advice about DVLA refusing to let us tax our vehicles? Their advice was to keep the vehicles off the road and follow complaints procedure. We are already 4 months into the process and tax runs out imminently. Feel really stuck as trying to do everything above board.