Why my first DirectDebit eMandate billing is RM1 lesser than actual recurring amount?

During the DirectDebit eMandate enrolment process, you have paid RM1 up front via FPX . Therefore, your first DirectDebit eMandate billing amount will be deducted RM1. For instant, if your recurring amount is RM100, then your first deduction is RM99 and subsequence is RM100.