Hi All, 

I hope you're all doing well during these difficult times. 

I recently installed a Deco mesh system in my house with 3 units, one main and two slaves that are all wired using cat-6 cables. 

THE SYSTEM IS WIRED IN THE METHOD BELOW:

• MODEM
  • MAIN DECO M5
    • TP-LINK TL-SG1005D (SWITCH)
      • SONY SMART TV (connected to switch with 10 meters of cat-6)
      • DECO M5 SLAVE TERRACE (connected to switch with 20 meters of cat-6)
      • DECO M5 SLAVE OFFICE (connected to switch with 30 meters of cat-6)

DECO ADVANCED SETTINGS:

• IPV4: PPPOE
• IPV6: DISABLED
• LAN IP:
  • 192.1268.68.1
  • SUBNET MASK: 255.255.255.0
• DHCP SERVER:
  • START IP: 192.168.68.100,
  • END UP: 192.168.68.250,
  • DEFAULT GATEWAY: 192.168.68.1
  • PRIMARY & SECONDARY DNS: BLANK
• IPTV/VLAN: DISABLED
• MAC CLONE:DISABLED
• ADDRESS RESERVATION: NONE
• PORT FORWARDAING: NONE
• TP-LINK DDNS: DISABLED
• SIP ALG: ENABLED
• UPNP: ENABLED
• FAST ROAMING: ENABLED
• BEAMFORMING: ENABLED
• LED CONTROL: ON
• OPERATING MODE: ROUTER
• NOTIFICATIONS: ENABLED

• GOOD THINGS THAT HAVE HAPPENED SO FAR:
  • All decos have solid green lights and the iOS app says they are online and in good health.
  • The Sony smart TV is working and fast over ethernet.
  • I updated the main Deco and it has the firmware version 1.4.4

• BAD THINGS THAT HAVE HAPPENED SO FAR:
  • When adding the 2 slave decos, the automatic deco finder couldn't find them no matter how close I placed them to the main deco and I eventually had to installand connect them using the direct bluetooth method on the app once it failed enough times and gave me that option.
  • The firmware version on both the slave decos are 1.1.6
    • I have tried updating the decos through the app, but it says that my network is uptodate.
  • even though there is a green light on the slave decos, when I stand next to them my wifi doesn't switch to it from the main deco and sometimes cuts out altogether.
    • Either all my devices refuse to switch from one unit to another or the slave decos are not out putting any wifi signal. 

I do not have much experience with networks, wired or otherwise so I'm a bit dead in the water here.
 

Any help would be very much appreciated, my kids are going to begin their e-learning classes soon and I need to get this sorted beforehand.

Thanks so much in advance!