Cannot assign user to a role

Hi *,

i want to assign some new created users to some roles. But i am not able, to assign them to the default roles like "Administrators" or even to edit this roles. Also if i create a new role, i am not able to add/edit permissions of this role.

We use a free license of ESXi 6.5 and access directly with WebClient. Is this some restriction of the free version?

Thank you & best regards

Max