Price Lock Premium Increasing Every Month??!!

Set up a price lock account in August 2022 at R399. My debit came off and it was significantly higher (R609) then was told the R399 quote was never processed and the price lock account is actually R409. I have since checked my statements and I have been charged 4 different subscription amounts none which was R409. I am now being told that the price lock subscription is R439. This is not the quote I approved and I have this in writing from your team that my price lock subscription amount is R409.

Price lock means the price is locked at a set premium surely? So why are you charging me a higher subscription fee every month?

I would like my account be credited ASAP because this is *****ing.