Shewud review for Appointment Booking Cowlendar

Shelley used the app for 21 days then asked for a FULL refund which I gave her (without asking any question). I get it that some people are not comfortable with tech things even though i've tried to make my app as easy to use as possible but I know I still need to improve a few things here and there. Then she harasses me on the Live Chat of my app even though I told him the refund will be there on her next shopify bill (which I don't handle, Shopify does). Keep in mind all her messages were answered within 3 min on my Live Chat. Then she leaves me 1-star because... why not ? Then she never replies back to my numerous emails explaining her the whole situation and how I can't speed up the billing cycle because a month is 30 days and that can't be shortened. Honestly, I wish we could rate users the same way they rate us like on Uber app so my fellow app developers would not let this kind of person rated 1-star install their app.