Purchased a set of 2x Deco X55 Units to upgrade my existing network of 2x x20 units, and ideally reuse one of the x20 units as a booster in the corner of the house.

Both x55 units can't connect to the internet - solid red light when it should be connected.

Units work as connected unit, but can't be set up as a main unit

I have tried:

• Deco app - setup x55 as "Replace Main Deco". Process gets all the way through and results in no connection / red light at end
• Add x55 as a satellite unit to existing network, and attempt to change in app with "Set Main Deco" - again gets all the way through and results in no connection
• Factory reset everything and set up new network with x55 as main unit - again cannot connect
• Add x55 as satellite unit to x20 Network, update firmware multiple times, repeat above
• MAC spoofing of old x20 unit

Tried all of the above with both x55 units

Both x20 units are able to be set up as a main unit, and neither x55 can.

Ultimately I am currently running an x20 unit as my main, with two x55s as satellites. Obviously this is not an ideal setup.

Not sure what I am missing here. Strongly considering taking the whole lot back and changing system. Any suggestions?