Mongoose & unique field
Use dropDups to ensure dropping duplicate records in your schemas like;
var SimSchema = new Schema({ msisdn : { type : String , unique : true, required : true, dropDups: true }, imsi : { type : String , unique : true, required : true, dropDups: true }, status : { type : Boolean, default: true}, signal : { type : Number }, probe_name : { type: String , required : true }});And before running your tests, restart mongodb