If you've received a payment for an order outside of Airsquare (e.g. bank transfer), you can record it against the order in Airsquare.
How do I record a payment against an order?
Go to Commerce > Orders.
Find the order and click View.
Find the Payments section, click Add.
Choose the Method.
Enter the Amount.
Enter the Date (when you received payment).
You can optionally choose to Send "payment received" email to customer so they know you've received payment. It'll send them a full summary of what has been paid and what is outstanding.
If you have Xero connected, you can Add payment to Xero invoice.
If the order is now fully paid after the adding the payment, the order status will automatically change to Paid.