Patient Portal Invoice Documents

Situation
I am installing open EMR 6.1.0 and during testing I found PDF documents are not being rendered to the patient portal from within the post payments screen. The message is delivered to the portal but the PDF with the actual invoice is not being created.

Are there any settings or configuration options I need to review?

OpenEMR Version
I’m using OpenEMR version 6.1.0

Browser:
I’m using: Firefox and MS edge

Operating System
I’m using: FreeBSD 13 64 bit

Logs
Did you check the logs? I don’t know what logs to check for this.
Was there anything pertinent in them?
Please paste them here (surround with three backticks (```) for readability.
You can also turn on User Debugging under Administration->Globals->Logging User Debugging Options=>All