Upgrade from Glyphs 1.3 to 2+ from original App store purchase

I purchased Glyphs 1.3 in 2013 from the Mac App Store, so I have a license, but how do I activate that license with the new website version 2.0? I don’t actually have a license key. Please advise.

Going from 1.x to 2.x is a paid upgrade, you are eligible for a half-price upgrade. Please follow the upgrade instructions on https://glyphsapp.com/buy/upgrade. You will find everything you need to know under the headline ‘Upgrading from Glyphs 1’.