WioE5 RTC Syncronization is wrong?

I have a dragino LoRaWAN gateway with TTN and ChirpStack lorawan servers. I am trying to syncronize the internal RTC with AT+LW=DTR and then with AT+CMSG=“ping”. the RTC syncs up but with a wrong time, generally future time (about few mins to one hour (not is constant)), is the module rtc firmware bug? or something with the LoRaWAN server or gateway? I don´t have another gateway to test.