Settlement of account

Terrible service. My account was fully paid by my financial adviser, but somehow the wrong account number was given by their financial department. (One number was left out). Now it is struggled to find the money that was already paid in March to link it to my account. This is frustrating. If you phone them the phone just keep on ringing and if eventually the pickup, they off system. I even have sent them proof of the payment and still they cannot see that the amount was paid.