A while ago I bought a 3 pack to install in a friend's house as his WiFi was having trouble with 3 floors.

Setting up was straightforward except foe 1 unit that was reluctant to mesh.

Eventually it did , but after a few months it started behaving erratically and then dropped off.

after several visits when I could get it working for a few days and then it would fail we decided to call it quits and bought another 3 pack.

installation and set up worked first time and its all still working today.

Fast forward to today and I have unpacked the original 3 pack and tried to set it up in my house.

Base station set and connected to my router, first attempt.

First extension set up and linked first time.

Second extension. failure after failure after failure.

What can I do with this unit?

Resetting it has no effect. I always end up with a flashing blue and never a solid green.

The unit is obviously faulty and has been since new.