@MannIsm 

The way you draw the picture, it should definitely work. 

If you have multiple wired devices connected to the switch and they all experience loss of connection simultaneously, the suspect would be Ethernet cable between switch and Deco. Try different cable, check if it is properly (tightly) connected on both ends, connect Ethernet cable to different port on Deco and on switch.

Also, I am assuming you are using gigabit, not Fast Ethernet 100Mbps, TP-Link switch. While in theory it does not matter, in practice this might be an issue, even if unlikely one.

Finally, I am assuming you have been using this switch before, somewhere, and it was working just fine. Because, if you have not used it before, it might just be defective switch.

@Alexandre. 

Good to know that it should work. Thanks for that.

Initially i was using D-Link 5-port which kept going down way too often. 
I am using  TP-Link TL-SG105 5-Port 10/100/1000Mbps Desktop Switch now and it's happening less.
I will try the other M9 Port.
And you made me realize that there are too many points of failure. It might be because of the docking station that i network it through to. Ill simplify the connections and see what happens.

Thanks a lot ! Will report back if i find out why.