Data loss from gateway RAK7268c to Mosquitto

Hi everyone, this is my first post…

I have a problem with a RAK7268c gateway, my system is made up like this:

  • 1 RAK gateway connected to the Internet via Ethernet cable
  • 3 Milesight EM320 temperature/humidity sensors; data storage and resending data functions are enabled; sending to the gateway scheduled every 15 minutes
  • Mosquitto broker installed on a Windows Server 2019 in the cloud
  • 2 MQTT clients running, MQTT Explorer and one developed by me.

The problem is that sometimes I don’t receive data from one or more sensors.
For example I receive data for 2 or 3 days from all the sensors and then suddenly one sensor (not always the same) no longer sends data for a variable amount of time. In the meantime I continue to receive data from other sensors.
This happens identically on both MQTT clients.
I therefore exclude a problem on MQTT clients.
The Mosquitto log does not report any problems.
It is not a connectivity problem between the gateway, Mosquitto server and MQTT client, because I continue to receive data from the sensors.
If the sensors lose the link with the gateway they should resend the data.

Anyone have an idea what’s going on?

Thank you very much