fatal error log

I noticed this error in one of my log files today: CRITICAL Uncaught Error: Class ‘Allegiant_Notify_System’ not found in /home/carmen/public_html/wp-content/themes/activello/inc/welcome-screen/sections/actions-required.php:91
The site appears to be working just fine but I’m concerned about how severe this error sounds.

2018-08-24T20:40:30+00:00 CRITICAL Uncaught Error: Class ‘Allegiant_Notify_System’ not found in /home/carmen/public_html/wp-content/themes/activello/inc/welcome-screen/sections/actions-required.php:91
Stack trace:
#0 /home/carmen/public_html/wp-content/themes/activello/inc/welcome-screen/class-activello-welcome.php(400): require_once()
#1 /home/carmen/public_html/wp-includes/class-wp-hook.php(286): Activello_Welcome->activello_welcome_screen(’’)
#2 /home/carmen/public_html/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(’’, Array)
#3 /home/carmen/public_html/wp-includes/plugin.php(453): WP_Hook->do_action(Array)
#4 /home/carmen/public_html/wp-admin/admin.php(224): do_action(‘appearance_page…’)
#5 /home/carmen/public_html/wp-admin/themes.php(10): require_once(’/home/carmen/pu…’)
#6 {main}
thrown

Hi there,
Thanks for reaching out.
Relating to your query here, I do not suppose that error should cause any issues. You may just consider having it ignored.
Please let us know if you have any more questions.
Best Regards,
Support.