Thanks for your response.
Yeah, it's only happen for SMBs, other appliances using Gaia OS still fine.
I already using Smart console app on my computer, and even tried streamed smart console, but it's don't have the Device field to generate token:

Token only can generate using Smart-1 Cloud in Infinity portal, this option is not available on the Smart Console.
Resolved: TAC modified something in the our smart-1 cloud management services backend, and after services restarted the SMB GWs not get locked anymore, I able to regenerate token right now.
Thanks.