title: MongooseError: Callback must be a function, got [object Object] with findOne mongoose
body: <p>I have this code where I am finding a monitor in the database with these queries</p>
  <pre class="lang-js prettyprint-override"><code>        const monitorfind = await monitorschema.findOne({ Price: { $lte: Number(reqbody.price) } }, {Size: {$gte: Number(reqbody.size - 8)}}, {hz: {$gte: Number(reqbody.hz - 25)}}, {Resolution: {$gte: Number(reqbody.res)}}, {ResponseTime: {$lte: Number(reqbody.ms +4)}})
  </code></pre>
  <p>When I run the code, I get this error:</p>
  <pre><code>throw new MongooseError('Callback must be a function, got ' + callback);
            ^
  
  MongooseError: Callback must be a function, got [object Object]
      at Function.Model.$handleCallbackError (C:\Users\Sochum\Desktop\pickitly_web_main\node_modules\mongoose\lib\model.js:4924:11)
      at Function.findOne (C:\Users\Sochum\Desktop\pickitly_web_main\node_modules\mongoose\lib\model.js:2248:19)
      at C:\Users\Sochum\Desktop\pickitly_web_main\routes\monitors.js:23:49
      at Layer.handle [as handle_request] (C:\Users\Sochum\Desktop\pickitly_web_main\node_modules\express\lib\router\layer.js:95:5)
      at next (C:\Users\Sochum\Desktop\pickitly_web_main\node_modules\express\lib\router\route.js:137:13)
      at Route.dispatch (C:\Users\Sochum\Desktop\pickitly_web_main\node_modules\express\lib\router\route.js:112:3)
      at Layer.handle [as handle_request] (C:\Users\Sochum\Desktop\pickitly_web_main\node_modules\express\lib\router\layer.js:95:5)
      at C:\Users\Sochum\Desktop\pickitly_web_main\node_modules\express\lib\router\index.js:281:22
      at Function.process_params (C:\Users\Sochum\Desktop\pickitly_web_main\node_modules\express\lib\router\index.js:335:12)
      at next (C:\Users\Sochum\Desktop\pickitly_web_main\node_modules\express\lib\router\index.js:275:10)
  </code></pre>
  <p>How do I fix this?</p>