Connecting AC 1900 extender that was turned off during setup

[Reves3]

I discovered that extender was connected but powered down after I completed the wifi setup.
There are no light lit on the extender now when it’s on, but on I am supposedly all done with the connection and registration.
Also, I can’t seem to reactive the process again to redo it while the power is on in the ext.
Suggestions?

[plemans]

IF something is messed up, factory reset it and start over. 

Push and hold reset for 7-15 seconds whiles its powered on. 

then I'd follow the installation assistant guide (i prefer it over WPS)

https://www.youtube.com/watch?v=yJVklshxBMk