Hi there, I somebody can help me out.

The other day I say that my flat's Archer C2 v1 still has a very old firmware version. So I decided it's time for an upgrade. I tried both firmware versions Archer C2(EU)_V1_170207 and Archer C2(EU)_V1_160706, each of them again both using LAN and wifi to access the router and I followed the update manual but I keep running into the same problem: The firmware is uploaded, then the update bar slowly runs to 54 %, then very quickly to 100 % (maybe that's normal but I thought it's noteworthy) and then I'm directed back to the router's starting page which shows *drum roll* "Firmware Version:0.9.1 4.2 v0032.0 Build 160706 Rel.37961n".  Am I doing something wrong here? What can I do to make it work?

Thank you in advance! :)