No recieving join requests from device?

Hi

I have a end device and a gateway that have previously been used to successfully send up links to my network server (au1 cluster).

The gateway was moved about a bit and signal was lost. After sometime we placed the gateway very close (~10m away) from the end devices. After a week no join request was made by the device even though the manufactures have confirmed that the longest period between joins OTA the device will reeach is 2hr 45mins.

This is the end device:

Both gateway and device are using freq plan AS_920_923_TTN_AU
end device is using LoraWAN version 1.0.3

I wondering what configuration setting or factor could cause this device to stop trying to join all together?
Previously it was using LoraWAN version 1.0.2, could that cause the device to stop trying to join?

Any additional info that could help please let me know.

Thanks.

Is it transmitting at all, any sort of packet, on any frequency?

Is it even on?

Figuring out what it is doing by some means - UART log output, SDR dongle, watching power consumption for the pulse draw that represents transmission and the smaller one that would represent each of the following receive windows would be a start.

Ideally a node should not be too quick to try to join again, but should instead continuing periodically transmitting useful measurements in the existing session. Remember, joined sessions exist between the node and the TTN servers, not between the node and any given gateway.