@manjulapra 

Thanks for the feedback.

Have you made any changes to the Deco network, like a Deco APP upgrade, or a new device join-in?

Could you please help me submit the APP log:

How to submit Deco APP log

" I noticed a bunch of devices (including the ones in those notifications) are shown under the "Guest" tab in the app, which indicates, according to the app those devices have joined the guest network. My guest network has a different SSID, and password, and these devices do not have the credentials to join the guest network. "

Are "those devices", like the two laptops actually connected to the main network but APP said they were connected to the guest network?

Have you checked the wireless settings on those devices individually? 

Wait for your reply.

Best regards.