Resync Invoice Feed when Sales Order Completes

Hello Team,
Need to ask a question related to pushing feeds from Woo-Commerce to Zoho Inventory.

I have setup following multiple feeds

– Contacts
(created when order is in processing)

– Sales Orders
(created when order is in processing. Linked to contact feed via “Assign Contact” required mapping)

– Invoices
(created when order is in processing. Linked to contact and sales order feed via “Assign Contact” and “Assign SalesOrder” required mapping.)

– Payments
(created when order is in completed state. Linked to contact and sales order feed via “Assign Contact” and “Assign Invoice” required mapping.)

Question 1:
How do we mark the invoice as paid when the order completes? Since I am creating the invoices when order moves to processing state. Also which field can be used for showing invoice status in zoho inventory?