Approval can’t be on while payment is on and payment can’t be on while approval is on.
In the PJ system, the user makes an order and then the order gets approved. Since the payment gateway appears during the checkout procedure, it makes little sense to allow an order to be paid for, then to send it to the approver. If the user has paid for it, then it goes to someone who rejects the order, there would have to be a refund. This is a complicated and messy business, which we’d rather avoid.
The solution is to not allow both to be on at the same time.
You might think it could be done by asking users to approve things before they get to the basket, but this method would conjure up all sorts of logical inconsistencies. We could also make it so the user couldn’t checkout the basket until someone has approved it, but then any update in the basket would require additional approvals etc. Also messy. If someone needs to intervene in order for an order to take place, and then a payment, the approver may as well make the order themselves, or the approval process could happen offline ‘Can I order this please?’.