Cannot purchase Razercare Essential because my system's serial # is not valid?

I go here: https://www.razer.com/razercare/warranty and enter the serial on the bottom of my razer and says not valid. My bios is missing the serial # (which sucks as I cannot upgrade to newer bios without a valid serial). I recall someone on reddit with an app that would hack your serial into the bios via a dos program. Any thoughts? My screen is flickering and I am stuck overseas and my warranty runs out in like 32 days. I sent an support email about 2 weeks ago, no reply yet.