No assistance whatsoever!

I have been trying since February to cancel my son's policy- as he is in a recovery centre as from then. but all my emails and phone calls are just ignored or brushed off. I did sent certified documents of my son's situation. and still they will not cancel the debit order with the bank or cancel the policy. He is not allowed to leave the recovery centre, or make any phone calls - so he is NOT capable to sort out his finances. I even have a power of attorney letter for the bank. but nobody is willing to assist me. NO RESPONSE ON MY EMAILs -SENT AS FROM FEB 2024, FOLLOW-UP IN MARCH!! NUMEROUS ATTEMPTS TO MAKE AN ARRANGEMENT, BUT ITS LIKE HITTING A BRICK WALL.