Cancellation of membership with THC (The Holiday Club)

My dad has been trying to cancel his membership since mid 2020 and has been unsuccessful. He was given incorrect information to begin with, advised to use the points prior to cancellation and told no new fees would be due and then out of the blue he is invoiced and subsequently handed over to attorneys. I act on his behalf and have given the reasons for cancellation (he is 73 and no longer interested in travel). We just want to cancel with The Holiday Club and end the relationship with them.