H&M shocking customer experience

So I had the worst experience at H&M Canal Walk. After purchasing items from the store on Monday 24th December I went to pay for these at the till point located in the Mens Wear section of the store. After paying for the items (@18h05) the cashier gave me the till slip only and not my bank card nor the speedpoint slip. She looked at me and smiled at that point. I left the store and drove home to Hout Bay. It was only then that I realised that my card was missing. It was 20h30 by this stage. I called the H&M customer service number advertised on their site until 21h00 to no avail. I called again and again on 25th December again to no avail. On Wednesday 26 I drove back to Canal Walk and on entering H&M asked to speak to the store manager. After waiting for appoximately 15 minutes a young man approached us and said he was the store manager. He did not immediately introduce himself. Only when asked did he tell us that his name. After explaining my story he called a colleague who initially said my card was not there after some discussion (me threatening to lay a charge at the police station) my card was suddenly produced. I asked the manager whether he thought it appropriate for the cashier/ sales assistant to behave in this manner and whether I was correct to infer that the card had been withheld deliberately - i had walked slowly out of the store on the 24th giving the salesperson ample opprtunity to call out to me/ follow in order to hand my card back to me. In short I am annoyed at the cavalier attitude of the store manager who basically informed me that he saw no reason to give me any further feedback on how this had happened and what steps the store would take to ensure that other customers do not have similar experiences. He did not even bother to write down the till slip ref number which would have helped him identify the H&M employee who had worked on the till that evening. I am shocked and outraged at what I percieve to be a reckless attitude with customers bank cards. In this day and age of digital *****, cloning of bank card details etc it is truly shocking to be told that youre not even owed an apology. Shame on you H&M, shame on you!!