No procedure nor efficient support to terminate unnecessary Premium support level & abs

Hello Dears,
After several unsuccessful exchanges with the support regarding a request to terminate the unnecessary Premium support subscribed in 2021 and billed 50€/month since then without any possibility to easily unsubscribe. I uploaded 3 times all requested documents (ID card & company details) on Plix. They were never treated on time => disappeared.
Today the ticket has been open for 1 month and is abandonned without follow up.
In between I was charged one additional month for nothing.
Any help is welcome to unblock this situation. All details & evidences can be provided if needed.
This is my last trial to find a solution.
I come to the conclusion that the only way for me to avoid paying monthly for nothing is to unsubscribe all my services from OVH and chose another cloud partner and ask a lawyer to recover the amounts unduly paid...