Most likely dead board. I had a dead board last week.
Guys, do you have problems with any of your L3+ hashboards? Second hashboard shows different number of chips (2 or 20 but not 72) and has only "xxxxxxx".
How long did you guys run your miners?
What temp did the chips have and did you overclock them?
Do you have them at home or in a data center
Restart does not help.
Miner was running only one week without any overclocking. Temperature on chips was around 61-65 C. I have it at home.