If you are no longer able to access your OVH server via SSH as the root user, you may consider using rescue mode to reset the root password, or edit the configuration files required to regain access.
Please keep in mind that cPanel is a separate company from OVH and we are unable to assist with tasks involving OVH networking, servers, and software. The following information is provided as a courtesy.
If you have a VPS with OVH, you may use the following guide:
How to Recover your OVH VPS in Rescue Mode
If you have a dedicated server, you can use the following guide for activating rescue mode:
Activating Rescue Mode on a Dedicated Server at OVH
If neither of those guides are helpful, you must reach out to a systems administrator for further assistance. cPanel support is not able to provide any sort of access to any server. You can review the following guide for information about finding a systems administrator: