Tymebank dissapointment

Good day I am a 63-year-old retired lady. I was looking for a bank to put in my social pension that does not charge a lot of fees. I came across Tymebank, and was pleased to see that their fees were much lower than most banks. I then transferred money into the account. On the 1st of April, I purchased R50 MTN airtime online. I noticed that another R50 was taken off as well. I thought, oh well let's leave it at that, so I expected R100 airtime from my service provider. To date, I have not received the airtime. The bank sent me "supposed" proof of purchase and payment. MTN let me know that the references and serial numbers were invalid. Tymebank refuses to refund my money and expects me to investigate and see why I did not get the airtime. Moving on, two weeks later, I get an SMS from "Tymebank" with a verification code to get my vouchers. Me, thinking that it was my airtime vouchers, opened the link, not knowing that it was a ****. Two days later, R1000 and R500 airtime respectively was taken off from my account for two separate cell numbers. I contacted the bank immediately. They said that they would investigate. A day later I received an SMS and email warning of this latest ****. Well, my money was already taken out. Firstly, how did the ******** know that I banked with Tymebank, and how did they get hold of my cell number?? That means that the bank's security was breached. After their investigations, I was told that I would get no refund!! I am so furious. They did not even consider my dilemma, being a pensioner and how each and every penny counts. I cannot believe the treatment I got. I am so disappointed in them. No airtime and no refund....so sad.