@Turnkey 

Try to forget the network on the Android phone first and reconnect it to the Deco M5. 

Besides, you can disable fast roaming, change wireless settings (including wifi name and password) to give it a go. 

Try to reboot the phone as well. 

Any updates, please let us know. 

@Turnkey 

Thanks for your reply. Then please provide the information below so that we can do further analysis. 

1. The model number of the Samsung phone and its OS version. 

2. The Deco app version. 

3. The current network diagram; besides, you can simplify the network--connect the main Deco to the modem only and verify whether the two phones can connect to it. 

4. Can they detect the Deco's wifi network? Or they can see it but failed to connect to it? Any error message pops up? 

Thanks in advance. 

@JustinP 

Hi,

Would there be any error message when Android failed to authenticate？

What are the model numbers and operating systems of those Android devices?

Did this issue start just after the firmware upgrade?

Have you added any of these devices to the blacklist?

Thank you very much and wait for your reply.

@JustinP 

Hi, thanks for the update;

For these devices(Samsung S6 & S6 edge（Running Android 7）+iPhone 12), I guess that they randomly got the error with ‘cannot authenticate’ and could not connect to the internet;

And most of the time, they connect to the Wi-Fi and work fine?

(So, it is more like these devices would drop the internet connection occasionally and reported with the not-authenticate error; )

If yes, how often did this issue occur?