Cannot add fields in Chronoform 6

I cannot add new fields, when I create a form. A new field's label, name or id are not updating on the field header like they are showing in the demo forms designer views.
After Quick save, the modified values will show in the editor view, but after Full Save (or Close) they disappear.
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I am using:
- Joomla 3.9.5
- PHP 7.2.17 (max_input_vars -> 5000)
- Firefox 67 (or Chrome the same issue)

Thanks for the update package, yet my system is not sending emails, although I replicate the Basic Contact Form demo settings.

Now I am receiving emails, sorry for the above comment.