Fillable PDF fields blank unless I click on them, show blank when printing

Overview

I am automating a workflow where responses from Microsoft Forms (saved to Excel) are used to populate a fillable PDF. At the end of each day, Power Automate will email the completed PDFs to recipients who will need to print and send them via snail mail.

I have successfully extracted data from Excel and filled in the PDF using Python. However, the issue I’m facing is that the filled fields appear blank unless manually clicked on. Worse, when printing, the fields remain empty.

Troubleshooting Steps Taken So Far

• Extracted form fields into an .fdf file and manually imported it into the template PDF. This correctly fills the fields, so I know that the first input of the data worked. However, manual intervention is not an option—I need full automation.
• Changed the font for all fields, as suggested in this post, but this did not resolve the issue.

Ideal Outcome

• The PDF should be automatically filled with the extracted Excel data.
• The filled values should be visible immediately without clicking the fields.
• The fields should be printable without disappearing.
• The process should remain fully automated, with no manual steps required.

I know the scope of this question lies a little outside of just Adobe Acrobat, but the main issue I'm having is the filled fields "disappearing". Any insights or suggestions would be greatly appreciated! I have attached a sample PDF with the disappearing field issue. Thanks in advance!