A payment can pass through an operator and a payment provider before it reaches its destination. Processing by one party and receipt by another are separate stages.
Bank processing, security controls and the payment method can affect timing. A payment reference and the date of the transaction can help trace a delay without submitting a duplicate payment.
When a payment does not appear
Look at the transaction status with your payment provider and keep any reference number. A pending transaction has not necessarily failed, and making another payment can create an unintended second deposit.
For a withdrawal, allow for both processing and the receiving institution's handling time. Account verification or incorrect payment details can also affect a transaction's progress.