I had similar issues. I fixed it after several failed attempts.
I followed this guide:
Hold down keys fn+esc and power up the laptop, when the power led begins to blink release the two buttons and press the power button just once, observe the usb stick flashing indicating it's flashing the bios, please note this can take a few attempts, I once struggled for a few hours until I finally tamed the beast :)
be patient okay
--> From this statement I saw that it can be tricky to get the new BIOS to load. One more try, this time pressing the power button just once AFTER I released the fn+esc keys, and voila!