Ninety One Investec avoid at all costs

I have been trying for 3 weeks to change the account that they pay a monthly income to. Every second day there is a new obstacle placed I my way to verify my ID it is not enough to go through security questions on they fone - there are requests to send docs to an IT mailbox, which just bounces them back. A selfie of me holding my ID...nothing is good enough. .it is absolute nonsense that if you have a retirement annuity you are forced to stay with the service provider for your lifetime (to experience ongoing poor service) . If anybody has any suggestions to assist me, please help - I am desperate