Since there is no "CID Font F1" file to download, try these workarounds to see or edit your document:
: Open the PDF in Adobe Acrobat and go to File > Properties > Fonts . This may reveal the "Actual Font" mapped to the F1/F2/F3 tags. Cid Font F1 F2 F3 Free Download
The gold standard for open-source CID-style fonts. IPA Fonts: High-quality Japanese fonts available for free. How to Fix Missing CID Font Errors Since there is no "CID Font F1" file
You can try downloading the Cid Font, including F1, F2, and F3 variations, from various online font repositories. Some popular options include: and F3 variations
If the document uses CID fonts, it often requires the . This is a free, official download from Adobe that adds support for various Asian and extended character sets.