I use 3 networks in my house , one is BELL FIBE network ( 2,4G and 5,0G) and the 2 other ones are extended network TP-LINK RE-450 and TP-LINK RE-650 which work on 2,4G and 5,0 G.

These 3 networks work well with all my devices ( PC, iPhone, iPad, smart TV, printer, etc) in my home 

I succeeded to link 4 Kasa mini plugs EP10 with TP-LINK 2,4G RE-450 but I was not able to connect them using my original network BELL FIBE and TP-LINK 2,5G RE-650 and I'm trying to find why.

I tried to connect KASA devices with these networks many times, changing often distances between KASA devices and modems without success.

So If somebody knows why KASA mini plugs can't connect with these networks but can with 2,4G RE-450, please help me.

Best regards