How do you close a partially paid invoice as the remainder of payment has been added to a new invoice?

Hi Sonmiru, 

Thank you for reaching out to us for this query. 

Basically, you cannot close an invoice if there is a balance in it.

If the remainder has been added to a new invoice, I suggest to amend the original invoice and remove the remainder otherwise it will be duplicated. 

Once you have amended the invoice to only reflect what's paid then the status will change to "Paid". 

Please let us know if you have further questions regarding this query.