When a user sees "CID Font F1" in a font list or error message, it means the PDF viewer has encountered a CID-keyed font referenced as object #1, but it may be missing the data describing which specific typeface that font is supposed to be.
Because these are just labels, you can't "download" them from a font site. You need to identify what the real font was and install that instead. How to Identify the Real Fonts in Your PDF cid font f1 f2 f3 free download high quality
You can try downloading the fonts from the following links: When a user sees "CID Font F1" in