Really unfortunate that Enpass has descended to low competence and seeming dishonesty about its problems. I have 6.8.4. Syncing via Dropbox was broken for both IOS and Macos. After 1.5 hours, I have everything working again. But, I have no idea why it ever broke: AND ENPASS WON'T ADMIT WHY--likely because they don't know either. I uninstalled on IOS. I backed up on Macos. I uninstalled on Macos. I deleted the Enpass folder at Dropbox/Apps. Reinstalled on Macos. Loaded the data from the recent backup. Synced to Dropbox. Worked. Reinstalled on IOS. Synced to Dropbox worked.
Along the way there were repeated failures to "authenticate" the app with messages to the effect (I forget the verbatim) "Unknown error. Authentication Failed. Try again later. That is an "f-u" error message if ever there was one. But, it had magically worked. Whatever.
Very disappointed. Now that Enpass has a subscription, maybe it's time to go back to OnePassword's evil subscription.
You could come clean and explain why the problem happened and apologize. This product is complicated with multiple sync servers and services, sales by the app store and on your website, and a feature-based subscription model. Test, test, test--outside the dev. lab in the wild world. You can't break synchronization. It's only the single most important feature. Your "work around" did work, but it was brute force: do everything over again. That's the solution for when the developers don't understand their product.
Like to here from Enpass about its intentions to do better.