Thanks for reaching out to us today, @userfinance4.
I have some information about linking paid invoices to a project. You'll need to create the invoices from the project page, or create it to link the transaction. Thus, adding the paid invoices to the project is unavailable.
To add it on the project page:
To create an invoice outside of the project page:
For more information about projects, check out these guides:
In case you need help with other customer tasks, click this link to go to our general topics with articles.
I'll be around if you have other questions or concerns. Just drop in the reply section below and I'm more than willing to answer them for you. Take care and have a great day ahead.