Missing Illustrator Layers After Exporting the PDF

[craftyType]

When I save a PDF from Illustrator, some of the layers are missing in the PDF. Any suggestions would be greatly appreciated!

• I'm working on a MacBook Pro running Catalina 10.15.7
• Illustrator 2021 (25.4.1)

This is what my Illustrator file looks like:

This is what the pdf file looks like:

This is what Finder shows me when previewing the pdf:

I've been wondering whether the issue is whith Illustrator or Acrobat but can't find a solution either way.

I've saved the pdf with the "Preserves Illustrator Editing Capabilities" and "Create Acrobat Layers from Top-Level layers" options both turned on and turned off whithout any noticable differences.

[Ton Frederiks]

Is the Blue set to Overprint? And what is the preference setting in Acrobat for Overprrint?

[craftyType]

Thanks for your help.

The Overprint Fill is not selected in Illustrator. This is what Overprint Preview looks like:

In Acrobat, the Overprint Preview is set to Always:

[Kurt Gold]

Can you show the Layers panel in Acrobat?

Can you perhaps even share the original Illustrator file (.ai)?

[craftyType]

Here are the layers in Acrobat:

I am unable to upload the .ai file. I'm getting the error "The attachment's binaryposter-36x24.ai content type (application/postscript) does not match its file extension and has been removed." 

It's an Illustrator file and I can open it in Illustrator. Not sure why I'm getting the error.

[craftyType]

I tried uploading two other Illustrator files but those too were removed

[Larry G. Schneider]

You will need to upload the file to something like Dropbox, Google Drive or the Creative Cloud and share a link here.

[craftyType]

Thanks for the tip Larry! I was able to upload and provide a link to my file.

[craftyType]

Here is the Illustrator file - https://shared-assets.adobe.com/link/e813ba1d-92ca-4fbf-4a35-216ea8bdeeef

[Ton Frederiks]

Looks fine for me. Ignored missing links, changed the missing font, but after that just saved as pdf with the default settings.