Hi. I thought it would be a nice idea to use credit card on daily basis to earn points and put the money on saving account instead. When salary was paid I covered my say -1500. A few days later I’m checking and I’m minus (say 300) and I didn’t spend that much I look at transactions the sums don’t add up, so it must be something that wasn’t there when I was paying 1500. I cover that exact 300 again and now I have positive 100 balance . Numbers are estimates not exact. What is going on please? It’s only been a few months since I’ve been using credit card this way