CGroup Limits

Hello,
This is my first post here and I am not sure if this is the correct section.
We have a dedicated server with cwp pro and 128GB of ram, but when I try to limit a user to more than 32G in Security > Cgroups resource limits, it says "error of limit".
Is there a limitation on the maximum ram you can allow a user to use?

Thank you in advance

it's probably 32GB per user, why do you need more for that user ?

Its a reseller account with a lot of domains, and I want to limit the total ram of its sites use. I thought of allocating half of the system ram for that account.

this is per account limit, meaning that it will limit each account and not a reseller since the reseller account is not consuming server resources as a system user.