It's possible you've selected the Bill this customer option, salves9.
The open invoice won't show once you select to bill the transaction to the sub-customer. Then, you enter the parent name when receiving the payment. You can verify this by going to the sub- customer's profile. Here's how:
- Select Customers from the Sales tab.
- Select your sub-customer.
- Verify the Bill this customer option under the Is sub-customer section.
- Click Save.
If you bill the sub-customer, make sure to select their name when recording the payment.
Please don't hesitate to let me know if you have other questions. I'll get back to you as soon as possible.