Failed orders but payment going through

[matburnham]

I've forced django-oscar-paypal onto django 4.2 with 24e1477 but am now finding about 20% of my transactions are failing to create an order, yet still making a payment in PayPal.

I've managed to get a screenshot of the error message:

Grateful for ideas of where to start to try and debug as it keeps costing my PayPal fees to refund erroneous transactions and I'm then having to recreate the original order manually.

[matburnham]

Having dug, I think this is a state problem with old django-oscar carts being in the open state despite having been used for previous orders. See django-oscar/django-oscar#4246.