Bank transfers are confirmed by a person, so they are not instant. The flow:
1. Open the invoice and choose bank transfer. The page shows the account details - use your INVOICE NUMBER as the payment reference, it is how your money finds your invoice.
2. Send the transfer at your bank.
3. Tell us on the invoice page that you paid - attach the receipt if you have one.
Your note lands in a review queue. When the transfer is confirmed, the invoice is marked paid and anything waiting on it proceeds. If the amount differs from the invoice - a partial payment - the invoice stays open for the remainder.