Monthly premium overpayment

My pensioner dad has a funeral policy with liberty he is paying R900 per month. Beginning of this month he mistakenly transfered R900 via banking app and when he went to them to get help getting his money back they are sending him from pillar to post going in to their offices in vereeniging at first they said he should go to the office after a week, he went there on Friday 12 July and again they telling him to go back next week. I mean how is he able to do all these up and down when half of his grant is with them, what is so difficult in just them refunding him the extra that he mistakenly transferred to their account?