If you've encountered this issue, please check the following:
1) At the point of transfer, your balance is sufficient (is greater than or equal to the scheduled amount) to transfer.
2) The recipient account is still active.
3) Your account is not closed. If you have closed your account, all scheduled transfers will automatically be cancelled.
4) The scheduled date exists within the month of your scheduled period. For example, if you have set it on the 31st during the month of February, the fund transfer will automatically take place on the 28th or on the last day of the month.