gistfile1.txt

[HttpPost("SignIn")]
public async Task<IActionResult> SignIn(UserLoginDTO userLoginDto)
{
    var user = _userManager.Users.SingleOrDefault(u => u.UserName == userLoginDto.Email);
    if (user is null)
    {
        return NotFound("User not found");
    }

    var userSigninResult = await _userManager.CheckPasswordAsync(user, userLoginDto.Password);

    if (userSigninResult)
    {
        return Ok();
    }

    return BadRequest("Email or password incorrect.");
}