MongooseError: Cast to ObjectId failed for value "5c4979f71703a803c803437d\t" at path "_id"
    at CastError (/work/webapps/g_1862/g_web_1862/node_modules/mongoose/lib/error/cast.js:26:11)
    at ObjectId.cast (/work/webapps/g_1862/g_web_1862/node_modules/mongoose/lib/schema/objectid.js:147:13)
    at ObjectId.castForQuery (/work/webapps/g_1862/g_web_1862/node_modules/mongoose/lib/schema/objectid.js:187:15)
    at cast (/work/webapps/g_1862/g_web_1862/node_modules/mongoose/lib/cast.js:229:32)
    at model.Query.Query.cast (/work/webapps/g_1862/g_web_1862/node_modules/mongoose/lib/query.js:2983:12)
    at model.Query.Query.findOne (/work/webapps/g_1862/g_web_1862/node_modules/mongoose/lib/query.js:1393:10)
    at Function.findOne (/work/webapps/g_1862/g_web_1862/node_modules/mongoose/lib/model.js:1303:13)
    at Function.findById (/work/webapps/g_1862/g_web_1862/node_modules/mongoose/lib/model.js:1231:15)
    at async.waterfall.mongoose.categoryModel.findOne._id (/work/webapps/g_1862/g_web_1862/routes/game.js:324:40)
    at nextTask (/work/webapps/g_1862/g_web_1862/node_modules/async/dist/async.js:5070:14)
    at Object.waterfall (/work/webapps/g_1862/g_web_1862/node_modules/async/dist/async.js:5073:5)
    at async.waterfall.async.parallel.mongoose.gameModel.find.$or.category.0 (/work/webapps/g_1862/g_web_1862/routes/game.js:321:19)
    at nextTask (/work/webapps/g_1862/g_web_1862/node_modules/async/dist/async.js:5070:14)
    at Object.waterfall (/work/webapps/g_1862/g_web_1862/node_modules/async/dist/async.js:5073:5)
    at /work/webapps/g_1862/g_web_1862/routes/game.js:318:11
    at Layer.handle [as handle_request] (/work/webapps/g_1862/g_web_1862/node_modules/express/lib/router/layer.js:95:5)