Old Mutual debits my account on the wrong date and they fail to Assist after I tried to make changes to my debit order date several times

I have a funeral Policy which I only insured my brother, basically I’m only a premium payer, but they failed to assist me when I requested to make changes to the Debit Order dates and was told my brother is the only 1 who can make changes however the Agent that assisted me to that take the insurance told me I have the privileges to make changes whenever I want. My brother called and they only made changes to the debit order date for 1 month ,Honestly I’m fed up with Old Mutual!!