No compatible constructor found for input type type `System.Ulid` HotChocolate

        services.AddGraphQLServer()
            .AddProjections()
            .AddAuthorization()
            .AddFiltering()
            .AddSorting()
            .AddQueryType<UsersQueries>()
            .AddMutationType<AccountMutations>()
            .AddTypeConverter<Ulid, string>(
                x => x.ToString())

this is my Extensions. What did I miss? I don't understand how can I make converter. I have tried to make converter from this Documentation but it is doesn't work

Can anybody help me?