incovenience

i do not have money in my account, I asked my sister to send me R 150, I go to the garage to get some petrol, when i swipe, my card declines, I ask her to send me another R 150, she sends it, then the card still declines. I check on my phone app, only to find out Nedbank took their debited their maintenance fee and another fee, which took all my money and put me in a negative. why do they charge me these fees before i am paid? they normally charge this fees on the 28th and i get paid on the 27th, i called their call centre and spoke to 2 consultants, the first dropped the phone when i asked to speak to management or the complaint department, the 2 nd consultant, didnt bother to call me back after my airtime was exhausted. i am stuck at the garage with no money to pay for the petrol. why are you inconveniencing us? i have been with nedbank for over 3 years and they always took their fees after pay day.