Auto and General Refuse to Cancel Deceased Policy -still deducting Premiums

My son was deceased in June 2021 .We only discovered in September this month that he had a car insurance policy with Auto and General. My wife called Auto and General yesterday 21 Sept to cancel this policy. She emailed the Death Certificate to them .Auto and General refused to cancel the policy ,insisting on a letter from the Masters court .She explained that the masters court is currently offline for the last three weeks because of IT problems and there will be a long delay in granting of executors letters. However, they refuse to cancel this policy insisting on deducting premium payments .This is downright dirty and a very poor reflection of you as a company .In fact what you are doing is *****ing from deceased for a car that's no longer being used. Surely a death certificate should be enough to cancel a policy .We have no idea how long it will take to get an executor letter ,whilst in the meantime Auto and general *****s money from my dead son. Can anyone out there please assist me as to how we could get this bunch of ******* at Auto and General to stop *****ing my sons money and assist on how we could terminate this policy??Any help will be appreciated