Very disappointed for my money going missing!!!

On 29 April 2019 I went to Fordsburg Atm to deposit money around 20:00pm, I was given a receipt saying transaction unsuccessful but my money was not returned or credited into my account, it was an amount of R19870, I then sent my wife to report the matter on 30 April 2019 as I was unavailable at the time to report it myself, she provided me with feedback stating the lady at the branch said that only R10000 surplus was found at the machine and that I was threatened into taking that R10000 or wait months for footage and other evidence to be provided before the final outcome.

Today she called and said she won't do any investigation only thing I need to do is to accept the R10,000 can someone tell me what's happening at this branch....

So tell me how the hell can I deposit R19870 and they only wanna refund me R10000??? Where did my other R9870 disappear to??? Or am I being ****med by the staff at Fordsburg wanting to eat my money?? These machines at this branch have been giving issues since they came into existence and yet nothing gets done, we being ****** daily for our money and yet we given such ******* service by this branch. Please investigate this matter further, I'm not accepting no R10000 when my initial deposit was R19870!!!!