Yesterday i had to reset my Archer C20 router. Also did a reset on my RE450 extender and ever since i did the reset either only my LAN connection to my extender works or sometimes i can get the 5ghz to work for a few minutes but the 2.4 never works... i have tried to do the setup through tplinkrepeater and tether with the same results, both 5 and 2.4 lights are on and the app and website tells me i'm connected to the router 

I can connect my things directly on the c20 wifi both 2.4 and 5 works but not on the repeater unless i'm connected via a LAN cable