Very much disappointed

I do not understand as to why Capitec can allow an amount over R1000 to go off on an online purchase where as the limit for on line purchases i have set is R100. I had booked a hotel and they did not say if the debit will go immediately as i am used to reserving with no payment , it stayed on my account as unprocessed until I called the bank to find out what was happening and found out they cannot reverse it, i spoke the hotel for them to reverse the money they said it will take 10 days, i logged a call with Capitec they told me it takes up to 30days for investigation. I want to know as to why the purchase went off in the first place when i have a limit of R100 and i want my money reversed immediately as i want to use it . I do not know how I should trust a bank that takes more than the limit or that allows an amount over the set limit to be used.