Transfer-Out of .FR Domain Hindered by Admin Contact Email

I purchased two .FR domains from a third-party company, who obtained them from OVH Company. Now, I need to transfer these domains to another service provider. However, there's an issue with the "Admin Contact Information" being set to a person unrelated to the third-party company.

Consequently, the third-party company claims they can't transfer out the domains because the EPP code is sent directly to the Admin Contact Email, which they can't access.

I've reported this to https://www.afnic.fr/, and they advised contacting OVH Team. I need to change the admin contact email and claim ownership of the domains using my authenticated documents. How can I proceed with this?