Write to ahoy@eggbag.llc. Include your phone and OS version and, if it’s about a day, the date and chord.

The notes are right but the shape doesn’t count.
Each day lists specific shapes. An open chord isn’t a CAGED shape, and an inversion only counts on the strings its slot names. Tap ? on the Play screen for the rules.
I missed a day.
A day counts if you finish it that day or the next. After that it stays in the calendar as a past day.
I bought Full Access on another device.
Settings in the app, then Restore purchase. It restores on the same store: an App Store purchase on iPhones, a Google Play purchase on Android.
I want a refund.
Purchases go through the store. Apple: reportaproblem.apple.com. Google: play.google.com, then Order history.