C＃-方法不包含对象的定义

Question

我有这段代码：

[HttpDelete("{id}")]
public async Task<IActionResult> Delete([FromBody] MonitorsDeleteRequest request)
{
    if (request == null)
    {
        return BadRequest("Request could not be parsed.");
    }

    if (request.MonitorId == Guid.Empty)
    {
        return BadRequest("Query Monitor Id is required.");
    }

    try
    {
        await monitoringService.RemoveMonitorAsync(
            new RemoveMonitorRequest()
            {
                MonitorId = new MonitorId(request.MonitorId)
            });

        return Accepted();

    }
    catch (Exception ex)
    {
        logger.LogError($"[{Request.Path.Value}]: {ex.ToString()}");
        return StatusCode(500, ex.Message);
    }
}

MonitorId方法（在等号左侧）内的RemoveMonitorRequest用红色下划线-Intellisense说“ RemoveMonitorRequest does not contain a definition for MonitorId.”

仅供参考，代码中的其他MonitorId都没有Intellisense错误。

该如何解决？