Deducting my account before i get paid

I have a loan with Capitec and the agreed monthly repayment is last day of every month but then capitec just deduct from my account before the agreed date and worse part is that they deduct even before pay day just today they just deducted now but i haven't received my salary as yet, i am thinking of changing bank now because they always deduct my account before pay day. i do not even know how i will get to work because they took my money which was supposed to last me until payday.