What's the best way solve this coupling between two types of classes

I have the following classes.

public class Container
{
    private ResourceA a;
    private ResourceB b;

    private List<User> users;

    public void handleUser(User u)
    {
        if (u is UserA ua)//cast into userA
        {
            ua.useResourceA(a);
        }else if (u is UserB ub)
        {
            ub.useResourceB(b);
        }
    }
}

public class User
{

}

public class UserA: User
{
    public void useResourceA(ResourceA a)
    {
        //do something with a
    }
}

public class UserB: User
{
    public void useResourceB(ResourceB b)
    {
        //do something with b
    }
}

ResourceA and B behave very differently. It's not possible to have a base class for the two of them. Yet UserA and UserB share some functionality and I need a list containing resource users for various reasons. I then also need to handle resource grant requests from the base class. So I have to cast them. Which is bad.

I thought about the following approach which solves the casting issue but couples the classes even further:

 public class Container
    {
        public ResourceA a;
        public ResourceB b;

        private List<User> users;

        public void handleUser(User u)
        {
            u.useResource(this);
        }
    }

    public abstract class User
    {
        public abstract void useResource(Container c);
    }

    public class UserA: User
    {
        public override void useResource(Container c)
        {
            useResourceA(c.a);
        }

        void useResourceA(ResourceA a)
        {
            //do something with b
        }
    }

    public class UserB: User
    {
        public override void useResource(Container c)
        {
            useResourceB(c.b);
        }
        public void useResourceB(ResourceB b)
        {
            //do something with b
        }
    }

Is this a well know anti pattern? Is there a better way to do this?