Accented characters missing in selected font in PDF form

[BNRW]

I have a PDF form, where I selected a specific font that must be used (i.e. Avenir LT Com). The font is legally installed on the machine and the PDF form is used only on that machine.

The font works in a form, except all accented characters are not in Avenir, but Arial, like the font doesn't have them - but it has.

I have used this workflow before and it worked for different non-standard font no problem, but for this and several others it doesn't work. Why it works for some, and why not for others? And why why why it works half-way, without accented characters?

I have Acrobat DC (CC subscriber) and Windows 7. Tried another machine with the same problem.

Thank you very much

[BNRW]

I have still this problem with another font... I am really desperate with this

[gkaiseril]

Are you using the unicode character numbers to enter the accented characters?

Using unicode characters by Thom Parker

[BNRW]

I am just typing the character on my keyboard the regular way. Lets say I am writing "rrrrr" and the form field correctly shows my font, but as soon I press for example "ř" then the letter "ř" switch to Arial or what.

It is seriously frustrating because I have licence for the font to be fully embeded and the font is "open". I have a little suspicion, that it might be because of .otf format. I am trying to investigate this, and open font in .ttf seems to work, but open font in .otf not.