Double charged for 1 transaction after initial declined due to their system

First and foremost I am not rating them with a star just not given an option to not rate. I went to Shell this morning to buy an item of R25, I tapped and after a while the system declined me as always assumption of insufficient funds🙄. I told the lady I know I have more than enough money but I went on my app and like I said I have more than enough funds.

So I inserted the card and it went through and when I got I see in contacts that I was charged twice now R50 instead of R25. I want to the garage and explained instead I was told it's nit them but my bank, my argument is that Shell wired the transaction to my bank and it honored the transaction. The lady tells me that happens and I told I've never had a problem with this before from any service provider or this Shell in particular and I live in the neighborhood and a big customer of them.

I tell the lady have a decency to apologize for the inconvenienced and explained that such happens and my bank will reverse the money in 7 working, but no she pushed her agenda and didn't see where I'm coming from.

She called the owner but instead of greeting me and asking what's the matter he says 'what's the problem'? I explain to him and her tells me that's my bank not him in an arrogant manner and he keeps on asking me 'what do you want me to do'? I repeated my self like a broken record and he was rude and told him 'oh well sorry it's your bank not me I don't have your money'? He goes on and on and making it my problem not his, he's not concerned and my frustration is both transactions are Ref Shell Sentra Motors Blomtuin! He was annoyed and told me to leave his shop as the tone was high and I reminded him that I've a been a loyal customer for years and this is the treatment I get. No common decency to understand my point and frustration but to push their agenda.

Please note I have never had an issue of a declined transaction going through, my very first experience was with SHELL SENTRA MOTORS BLOMTUIN!

I need assistance with this issue and will not lay it to rest.

Thank you