The charger may show “offline” due to a loss of communication.
There are a few things that you can do to reestablish communication:
SIM:
May have lost cellular connection to the tower.
If communication has not returned within 15/30 minutes, perform a power cycle on the charger.
Power-cycle it by turning it off at the circuit breaker for about 30 seconds and then turning it back on. This process of rebooting the charger will take about 1-3 minutes.
Ethernet:
Check the modem and ensure its connection and active data transfer are still on. A possible reset of the modem is necessary.
If communication isn't restored, you can contact your IT department and have them check if a firewall is blocking the communication.
Power-cycle the charger: Turn off the power at the circuit breaker for about 30 seconds and then turn it back on. This process of rebooting the charger will take about 1-3 minutes.
Wi-Fi:
The charger may have lost the Wi-Fi connection. Ensure no obstructions or walls exist between the WIFI router and the charger.
Reset the router
Power-cycle the charger: Turn off the power at the circuit breaker for about 30 seconds and then turn it back on. This process of rebooting the charger will take about 1-3 minutes.