Unable to pair SONOFF zigbee dongle lite MG21 with router mode firmware after removing it from zigbee network

I flashed my sonoff dongle lite with zigbee router firmware. after the firmware update was complete, it automatically joined my zigbee network.

Just for testing i decided to remove it from the network by doing a force remove in zigbee2mqtt. note that i did not block the device, and my device block list is empty.

I wanted to add it to my network again, but it no longer joins the network.

What I’ve tried.

  1. reflashed the dongle with router firmware again, did not work.
  2. reflashed the dongle with coordinator firmware, and then router firmware, did not work.
  3. used another seperate zigbee network to check if it will join that network, did not join.

How do i can I readd this to a zigbee network?