All Notes displayed as empty after Updating

All Notes displayed as empty after Updating

Hello everyone,

I'm mainly using the Notebook App on my good old iPad Mini 1 (yep, the one without a retina screen :D ). It always worked totally fine, but today I did the update to Version 5.2. Now suddenly all of my notes are empty (just the header of each note is there). Please let me know how to fix this or release an hotfix update, because I'm using your app happily at work for several years now.

Version 5.2
iPad Mini (1st Generation)
iOS 9.3.5