Extra Fields setup disappears

I need some help with the setup. I just purchased the Lifetime Starter package and am having issues with the new form. I had been using the free version for a while, and now that I purchased a license, I’m having issues with customization.

First, I can’t change the default extra fields. I would like to remove the required flag, but they’re not editable.

Second, once I submit the extra fields & leave the form settings page, when I go back to make more changes, there is nothing inside the extra fields section. It’s still showing on the site, but there is no control panel to edit my extra fields. I can’t even redo it because the fields pane on the right side doesn’t even show up.

Tech Details:
————

OS: Fedora 31
Browser: Google Chrome Version 83.0.4103.97 (Official Build) (64-bit)
WP: 5.4.2
Active Theme: Customizr 4.1.52
WP_DEBUG: Disabled
WP Memory Limit: 40MB

———— NIMBLE CONFIGURATION
Version: 2.1.0
Upgraded From: 2.0.15
Started With: 1.10.7

———— WP ACTIVE PLUGINS
All-in-One Event Calendar by Time.ly: 2.6.4
Classic Editor: 1.5
Embed Plus for YouTube – Gallery, Channel, Playlist, Live Stream: 13.4
Envira Gallery Lite: 1.7.8.9
Jetpack by WordPress.com: 8.6.1
Nimble Page Builder: 2.1.0
WP Easy Pay (Premium): 3.1.3
WPForms Lite: 1.6.0.2
WP Maintenance Mode: 2.2.4
YouTube Live: 1.7.15

———— WEBSERVER CONFIG
PHP Version: 7.4.7
MySQL Version: 8.0.17
Webserver Info: Apache/2.4.37 (centos8) OpenSSL/1.1.1c
Writing Permissions: OK

———— PHP CONFIG
Memory Limit: 256M
Upload Max Size: 50M
Post Max Size: 75M
Upload Max Filesize: 50M
Time Limit: 30
Max Input Vars: 1000

The page I need help with: [log in to see the link]