* 겪고 있는 문제 상황을 최대한 자세하게 작성해주세요.

* 문제 해결을 위해 어떤 시도를 해보았는지 구체적으로 함께 알려주세요.

Realtime Database 에 like 폴더 is not created.

작성한 코드 및 에러 메세지

[Unhandled promise rejection: ReferenceError: Can't find variable: user_id]

at node_modules\@babel\runtime\helpers\asyncToGenerator.js:null in asyncGeneratorStep

at node_modules\@babel\runtime\helpers\asyncToGenerator.js:null in _next

at node_modules\promise\setimmediate\core.js:null in tryCallOne  

at node_modules\promise\setimmediate\core.js:null in setImmediate$argument_0

at node_modules\react-native\Libraries\Core\Timers\JSTimers.js:null in _allocateCallback$argument_0

at node_modules\react-native\Libraries\Core\Timers\JSTimers.js:null in _callTimer

at node_modules\react-native\Libraries\Core\Timers\JSTimers.js:null in _callReactNativeMicrotasksPass

at node_modules\react-native\Libraries\Core\Timers\JSTimers.js:null in callReactNativeMicrotasks

at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:null in __callReactNativeMicrotasks

at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:null in __guard$argument_0

at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:null in __guard

at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:null in flushedQueue

Object {

 "key": "DetailPage-Bk0_I3Kz4sfVvegqoTOKK",

 "name": "DetailPage",

 "params": Object {

  "idx": 0,

 },

 "path": undefined,

}

Object {

 "key": "DetailPage-Bk0_I3Kz4sfVvegqoTOKK",

 "name": "DetailPage",

 "params": Object {

  "idx": 0,

 },

 "path": undefined,

}