Considerable amount of money hanging in mid air for 3 weeks. No resolution - despite all my efforts

I booked plain tickets with Delta and went through all the steps to make a payment. The money has been taken from my account but is currently hanging in mid air. Delta never collected the funds and booked our airplane tickets. I contacted Capitec that confirms they see the transaction but require a letter from Delta before they can release my money again. Delta just keeps on saying that they cannot provide me with a letter as there has been no transaction and they have not collected the money. Delta keeps on advising to contact my bank to release the money or wait until it falls off into our account again and the bank keeps on saying I need to ask Delta for a letter. I am extremely frustrated that my funds have now been hanging in mid air for 3 weeks. This has impacted my family in a huge way as our funds that we need to use to by tickets have been in midair. I am also loosing out on interest on top of this on money that belongs to me and my bank that is not willing to assist me as the client with my money despite all the calls I have made and all the explanations I have provided. I have even contacted master card that directs my call to Capitec and also no resolution. I also received no reference numbers for my calls. There is just no interest in assisting me as the client with my money. This has cost me more money as I need to phone from the US every time I need try and sort out this mess. Please note my number is a US number and +1 is the country dial code that you need to place in front of the number to make a successful call.