Honouring fee on a debit card purchase

I purchased items on the 1st of September with my debit card and for some reason it didn't debit on the same day but 4 days later and the account had insufficient money then because I dont regularly check bank statement because i was under the impression that i had funds in my account. Then on the 7th I deposited some money on the account. So i owed 4 transactions according to the bank statement R187.66 Items, R5.16 bank fee, R1.63 bank fee and R59.42 Items respectively and all of them took 131.14 which equal to R524,56 of honouring fee. So my question is if I didn't have money in the account why were the transactions allowed. Can you kindly get back to me because i need an explanation on why the transaction went through if i didnt have money. I believe this is just a rip-off. Please respond on my email address: **********