Do the received fcount values between such ‘inactivity’ show contiguous numbers or are there gaps in values (suggesting device may have transmitted but signal not captured - therefore not inactive just unheard).
Is the RSSI/SNR as seen in GW logs representative of a good quality signal (say RSSI -60 → -110dbm) - or is it low/close to edge of reception level (there may be periods due to interferers or blocking objects where it drops below viability) or even too high (keep decent seperation between GW & node - Forum search) if so avoid overload conditions leading to false/corrupted messages or channel bleed.
If power to node stable and GW online then likely one for the vendors support team/forum, unless periods of inactivity expected/documented; e.g. wont send if Delta values read and not above a significant value or hysteresis level +/- ……does vendor documentation have anything to say on that point?