Passport renewal Missing doc

Hey guys I have a question about sending the missing documents for VFS global for passport renewal.

Do we need to use our own shipping label or we can pay for the shipping label on the VFS website and use it for shipping?

Context:
I recently submitted for passport renewal to Houston VFS and I got a notification about the missing document. My passport preview page was empty. I re-printed it as per instructions and created another FedEx label through the VFS site and sent that application again. I have not received any notification that it is delivered or they started processing again. My document reached there on Thursday morning. When I look at the instruction on the tracking page it says I need to use my own label. When I look at the email I received they are saying I need to go through the VFS site and enter the Incomplete/Missing document category and generate label.