Cannot connect to Norns Shield Hotspot

I’m trying to connect a Norns Shield to another Norns Shield running a hotspot.
The network shows up on the Norns where I am trying to connect from, but the activation status never moves from “activating”. Moreover, the norns network disappears after a while.
I’ve tried in both directions, but with a similar result.
I’ve entered nnnnnnnn in the password field.

are you able to connect a computer or your phone to the hotspot?

No.
I get the exact same result.
It happens on either unit.

Same issue, cannot connect to norns shield’s hotspot via phone or mac.(But It worked before)
Also shield work good with Wi-Fi router.

Both of my units works perfectly when I connect them to the WiFi router, but Link synchronization between them does not work.