Re: Issue with the app.
As mentioned in our reply to your App Store review, we've only heard of this problem when people try to use the flick gestures instead of the dedicated buttons to exit the keyboard, and there's nothing we can do on our end to completely prevent this from happening in that case. If you do not need to access the control center from all apps, you could actually turn it off from the iOS Settings, and still be able to access it from the home screen. Here's a relevant article: https://www.engadget.com/2014/05/06/iphone-101-control-center-getting-in-the-way-heres-how-to-dis/
Hope this is helpful to you. If you can't turn off the control center and are still experiencing issues, we would be happy to learn more about the exact way you perform the explore gesture to find and activate the "Next Keyboard" or "Dismiss Keyboard" buttons, and we have some ideas on how we could figure this out together with a special build of FlickType that we can send you through TestFlight.