ASP.NET CORE 2.1 - FromQuery doesnt work?

I have class for capturing all parameters :

public class UserParams
{
    private const int MaxPageSize = 50;
    public int PageNumber { get; set; } = 1;
    private int pageSize = 10;
    public int PageSize
    {
        get { return pageSize;}
        set { pageSize = (value > MaxPageSize) ? MaxPageSize : value;}
    }

    public int UserId { get; set; }        
    public string OrderBy { get; set; }
    public bool isAll {get; set;} = true; 
    public bool isManagers { get; set; } = false;
    public bool isPartners { get; set; } = false;
}

and my controllers:

[HttpGet]
public async Task<IActionResult> GetUsers([FromQuery] UserParams userParams)
{
    var users = await _appRepo.GetUsers(userParams);
    var usersDto = _mapper.Map<IEnumerable<UserSimpleDto>>(users);
    Response.AddPagination(users.CurrentPage, users.PageSize, users.TotalCount, users.TotalPages);
    return Ok(usersDto);
}    

While my appRepo.GetUsers:

public async Task<PagedList<User>> GetUsers(UserParams userParams)
{
    var users = _context.Users.OrderByDescending(p => p.FirstName).AsQueryable();
    if(userParams.isManagers)
    {
        users = users.Where( u => u.IsManager == true);
    }

    if(userParams.isPartners)
    {
        users = users.Where( u => u.IsPartner == true);
    }

    return await PagedList<User>.CreateAsync(users, userParams.PageNumber, userParams.PageSize);
}

I tried to debug the code with Postman : http://localhost:5000/api/user?isManagers=1 or http://localhost:5000/api/user?isManagers=true

but it seems the params isManagers still false (the result is still get all users)

How to fix this bug?