FNB Rejected ***** claim in my account

Hello, My card was used at Avis van rental in March and i complained with my bank FNB and then the transaction was reverse because i didn't have money in the account and the following month April another transaction took place of R 22k and bear in mind that i had already cancelled my card at the bank issued with the new one and i contacted debit card dispute again and they rejected my query this time is my money not overdraft. on the 04 May i contacted the ***** division and they kept me waiting for 13 days till today when i contacted them they referred me back to card dispute who rejected me at first, Avis they could't find my details for the first time and the second time on Monday the 14 May they know the story now because i believe the bank contacted them but they said they will come back to me and again today i followed up with them still nothing has been done on their side. who can we trust with our money then.