Hi, Sanchez.
Since the invoice was sent on Saturday, processing would have begun on Monday because bank transfers do not process on weekends.
Payments processed through QuickBooks depend on the method your client used to pay (bank transfer, credit card, etc.).
Card transactions typically process instantly but may take 1 to 3 business days for the funds to clear. ACH or Direct Debit payments usually process within 2 to 7 days, depending on when the customer initiates the payment and the time needed for the bank's processing.
If you have any further questions or need assistance, feel free to comment below.