Vodacom deducting airtime but no service and struggling for refund

I made a Google play store payment for R79.99 on 11 December 2019 using my Vodacom airtime (bought with my bank card).

Vodacom declined my payment to Google play store but deducted my airtime. After several back and forth conversations to Google play store, it was established that Vodacom was the issue. I made 3x phone calls to Vodacom call centre. And eventually managed to get an email address. I email proof and I received email confirmation that my funds have been received by Vodacom . She promised to refund my airtime, but it has been 3 days now. Vodacom call centre blocked my calls when I choose to speak to a person due to numerous calls. I made 3 calls where I spoke to 3 different people each time. And I had to call the second time because they closed my case which I had a reference number but without resolving "Thank you for your support. Your query with ref number *** has been closed. Visit www.vodacom.co.za/help from your PC or cellphone. Thank you, Vodacom"

I tried Vodacom twitter and Facebook messenger contacts but they keep asking me for useless information like :"Hi Safiyya, In order for us to authenticate you as the legitimate owner of the account and access your profile, we would need you to answer the below questions via private message:

1) Debit order date 2) Bank name and type of account 3) Address on statement"

For a prepaid account!

I have pocket WiFi with them so I actually provided above details. Still nothing.

Speaking to Vodacom customer care is like a useless back and forth practise conversation about the weather! There is no communication between departments. They should have specialised departments to which our calls can be forwarded and dealt with efficiently. The people on the other end of the line know nothing about anything and tell you that they can't communicate with people within their organisation to get things sorted. Like my Google play store situation.