Exported pdf from Autodesk Inventor not showing correct Font in Illustrator

Hello, I am using Illustrator for finetuning exported pdf's from Autodesk Inventor.

For years i am doing this without a problem, but now whenever I open the PDF in AI it shows everything in Arial font.

I tried downgrading to different versions as this happened once in the past and had been solved with a downgrade, but this time nothing did work.

Autodesk Inventor did not have an update here so I really do not know why this is happening, I hope this is a known issue so it can be solved easily.

FYI, Inventor always exports as plain text (the font is somewhere embedded) and I always needed an intermediate step and open the PDF first in an editor for it to show the embedded font.

The font that I am using is a bought one, and also showing up in the fonts lists.

Thanks in advance,

Semih