AAF ISSUE FROM MC TO PT "Could not complete your request because an unexpected error happened while trying to find a media file's location. "

Hi editors,
i have an issue with an AAF from Media Composer (2018.12.2) to ProTools (2019).
When the sound editor open the AAF it comes out this message of error: "Could not complete your request because an unexpected error happened while trying to find a media file's location."
I've tried to export an AAF with the first 12 tracks (recorded sound) and it is perfect. The problem is with tracks from 13 to 20 (SFX and music). But the directory of these files is correct and we have no idea how to fix this.

Any idea, please? <3 Thank you a lot!

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