Unifi HG850a, Backup Unit

Hi Guys,

Recently I bought a used unit from the forum. Below is my issue.

i had bought another unit of HG850a and restore my configuration file from my original unit (UNIFI).

Before restoring, I try to replace the HG850a with the newly bought unit but the link light always blinking. After restoring the configuration file also the same.

Could it be that they had the MAC address coded in UNIFI router/server??

Is there any configurations that I need to do in the new(used) unit of HG850a? Or it is the unit is faulty? I can go into the configuration menu/telnet (instructions from the other post)?

Thanks guys.