Unexplainable bank transaction in my account!!!!

So, few days ago I discovered few transactions that don’t make sense on my account. The only reference to these is “#Items not paid”and states amounts. I had a huge problem with these because they go all the from June of 2021 (at-least because that’s how far I can look). Anyway I then follow up by going to the bank because the last one was few days ago for R180 and the other one was in Jan of R810 in Dec R136 and it goes on and on… What I then discovered talking to them is that when I went and bought something at a shop even thou the money goes off my account it will still be my responsibility to make sure theres more money in my account so that when the retailers do their banking in 3-4 days later they don’t find money in my account. And then I ask them, but what happens when that money gets off my account when I had paid at the shop and that references as money purchased or reserved for purchase at a particular store? This has happen for far to long and their explanation is something I can not comprehend at all. Because what happens to the money that gets off my account when I pay ? Why do I still need to have more money when the banking after 3 days happens???? I lodged a complaint and I was refunded Feb R180 and Jan R810 and when I told them there’s more of these I need to get cleared and refunded I was then told that it cannot be done. The refund I got was out of “good will” Whaaaaat???? Unbelievable.

I am still puzzled about this . I am truly unhappy and once I’ve completed this investigation I’m leaving this bank. I have been with them for over 15years.