TTN packet forwarder doesn't start after reboot

Dear,

I’m using Multitech Access Point mPower version.
Gateway setup using these guidelines : https://www.thethingsnetwork.org/docs/gateways/multitech/aep.html

When I use TTN account, there is no issue. After a reboot, the gateway reconnects to TTN platform.
When I use TTI account, there is no LoRa connectivity. I need to log in the gateway and restart the packet forwarder manually.

How can make sure the their is a LoRa connection with TTI account after a reboot?

Thanks and best regards,
Wouter