Calendar Event Reminder KEY

I've used this app for probably 3 years and generally like it a lot. At one point, however, it stopped sounding the alarm, so I uninstalled/reinstalled it. It started working again, but I lost quite a few of my calendar events. Recently it started giving me the alarm music doubled (starting about 3 seconds apart). After a couple of weeks of that, it now gives me no sound at all. Short of reinstalling it again, I'm not sure if there's anything else I can do. Any suggestions?

I've now got this paid version. Which is great, aside from the snooze being a bit glitchy. I changed a setting on my phone and it now works most of the time (not completely reliable, so that's not ideal). I've added the app to the list that isn't energy saved. So far so good. There are some tones which if you've downloaded them don't have permissions to be used with this app. I got some via Zedge and none work. Bit of a shame as they worked with my last alarm app. The free version is in my opinion completely pointless as you can't change the alarm duration and so it's a one sound alarm, which is the same as my phones calendar. I'll see how this goes. The developer responds quickly and tries to help.

I really appreciate it, but any time my phone storage fills up, it stops working until I clear my storage and uninstall and reinstall the app. Other than that, I find it a great extension to Google Calendar.