Error when attempting to save Theme Options with Virtue Theme & Ultimate Member

Greetings Ultimate Members support staff,
I encounter an error when attempting to save any setting on Kadencethemes: Virtue theme while the UM plugin is active. Error is shown below, followed by System Status. I deactivate the plugin to make changes to the theme options at present, but I imagined you all would want to be aware of the issue.

System Status
WordPress Environment
Home URL: https://sevc.yogat3ch.net
Site URL: https://sevc.yogat3ch.net
WP Content URL: https://sevc.yogat3ch.net/wp-content
WP Version: 4.8
WP Multisite: –
Permalink Structure: /%category%/%postname%/
Front Page Display: page
Front Page: Home (#2295)
Posts Page: Unset
WP Memory Limit: 40 MB
Database Table Prefix: Length: 3 – Status: Acceptable
WP Debug Mode: –
Language: en
Server Environment
Server Info: Apache/2.4.25
PHP Version: 7.1.6
ABSPATH: /home/yogat3ch/public_html/sevc/
PHP Memory Limit: 256 MB
PHP Post Max Size: 8 MB
PHP Time Limit: 30
PHP Max Input Vars: 1000
PHP Display Errors: –
SUHOSIN Installed: –
MySQL Version: 5.6.35
Max Upload Size: 8 MB
Default Timezone is UTC: ?
fsockopen/cURL: ?
Active Plugins (10)
AddFunc Head & Footer Code by AddFunc – 1.4
Duplicate Page by mndpsingh287 – 2.3
Inline Google Spreadsheet Viewer by Meitar Moscovitz – 0.12.4
Kadence Slider by Kadence Themes – 2.1.2
WordPress Media Library Folders by Max Foundry – 3.4.2
Photo Gallery by Photo Gallery Team – 1.3.48
Slider Revolution by ThemePunch – 5.4.5.1
Ultimate Member by Ultimate Member – 1.3.88
UpdraftPlus – Backup/Restore by UpdraftPlus.Com, DavidAnderson – 1.13.4
WP Colorbox by naa986 – 1.1.1
Theme
Name: Virtue – Premium
Version: 4.2.3
Author URL: https://www.kadencethemes.com/
Child Theme: ?