My deco remains on blinking blue ..

I have a deco unit  (m4R) which works fine and is connected through ethernet through ISP modem. Another deco device 'hallway' -  (E4R) connects through wifi and works fine.

I had another e4r that connects to the system (study) and removed it from the network i.e. deleted from the app (as this was the main deco).  I even log out and logged in the app. 

I am using the deco app to re-add it but still remains blue light (on/off) but the app cannot find it. If i check on my mobile i can see the SSID Deco_4D7C (which is the deco that i need to add to the network)

I restarteted the internet several times but still the problem persists.

I checked the following :-

1 Smartphone is connected to the Deco’s network.

2. The LED on the satellite Deco is blinking blue.

3. I can confirm there is an open SSID on the Wi-Fi list, as I can see it through the mobile

4. Open deco app but still cannot add the deco (kindly note that this deco was being used as a main deco but i updated to a new deco to M4R

5. Also Connected it via Ethernet cable to the main Deco also but still not working  that isp modem ethernet main and from one of the ports the deco that is not working

Any suggestions please?

Regards

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