Not reading RFID tag with Zebra FX7500 and EdgeX device-rfid-llrp-go

Question

I'm using the device service device-rfid-llrp-go for reading EPC tags data from different RFID readers. I'm having many problems with Zebra FX7500 reader with only two antennas attached(number 1 and 4). I'm sending a ROSpec.json file attached below, using the command.sh script located in the examples folder of this repository https://github.com/edgexfoundry/device-rfid-llrp-go#device-rfid-llrp-go.

{
 "ROSpecID": 1,
 "Priority": 0,
 "ROSpecCurrentState": 0,
 "ROBoundarySpec": {
     "StartTrigger": {
         "Trigger": 0,
         "PeriodicTrigger": null,
         "GPITrigger": null
     },
     "StopTrigger": {
         "Trigger": 0,
         "DurationTriggerValue": null,
         "GPITriggerValue": null
     }
 },
 "AISpecs": [
     {
         "AntennaIDs": [1, 4],
         "StopTrigger": {
             "Trigger": 0,
             "DurationTriggerValue": null,
             "GPITrigger": null,
             "TagObservationTrigger": {
                 "Trigger": null,
                 "NumberOfTags": null,
                 "NumberOfAttempts": null,
                 "T": null,
                 "Timeout": null
             }
         },
         "InventoryParameterSpecs": [
             {
                 "InventoryParameterSpecID": 1,
                 "AirProtocolID": 1,
                 "AntennaConfigurations": [
                 {
                     "AntennaID": 1,
                     "RFReceiver": 0,
                     "RFTransmitter": {
                         "ChannelIndex": 1,
                         "TransmitPowerIndex": 15
                         },
                     "C1G2InventoryCommand": {
                         "TagInventoryStateAware": false,
                         "RFControl": {
                             "RFModeID": 23,
                             "Tari": 0
                         },
                         "SingulationControl": {
                             "Session": 1,
                             "TagPopulation": 4,
                             "TagTransitTime": 1
                         }
                     }
                 },
                 {
                     "AntennaID": 4,
                     "RFReceiver": 0,
                     "RFTransmitter": {
                         "ChannelIndex": 1,
                         "TransmitPowerIndex": 15
                         },
                     "C1G2InventoryCommand": {
                         "TagInventoryStateAware": false,
                         "RFControl": {
                             "RFModeID": 23,
                             "Tari": 0
                         },
                         "SingulationControl": {
                             "Session": 1,
                             "TagPopulation": 4,
                             "TagTransitTime": 1
                         }
                     }
                 }
             ]
             }
         ]
     }
 ],
 "RFSurveySpecs": null,
 "Custom": null,
 "LoopSpec": null,
 "ROReportSpec": {
     "Trigger": 2,
     "N": 1,
     "TagReportContentSelector": {
         "EnableROSpecID": true,
         "EnableAntennaID": true,
         "EnableFirstSeenTimestamp": true,
         "EnableLastSeenTimestamp": true,
         "EnableTagSeenCount": true,
         "EnableSpecIndex": false,
         "EnableInventoryParamSpecID": false,
         "EnableChannelIndex": false,
         "EnablePeakRSSI": false,
         "EnableAccessSpecID": false
     }
 }
}

In particular I'm following these steps:

1. ./command.sh add ROSpec ROSpec.json
2. ./command.sh enable ROSpec 1
3. ./command.sh start ROSpec 1

After that I read that the ROSpecCurrentState becomes 2, that means "Active". In this way I should read the EPC value because I've added a Printf in the newROHandler() function of the device.go file, but nothing. I've also had a look to this link LLRP for Zebra FX7500 with llrpjs doesn't read tags, where there is a similar problem with llrpjs library. Can anyone give me a hand to solve this issue?