fatal error accessing appearance > theme options

Using ButterBelly Pro Responsive. From my dashboard, when I try to edit my homepage via “Appearance” > “Theme options”, I get a fatal error notification. Then I get this email detailing the error:

Howdy!

Since WordPress 5.2 there is a built-in feature that detects when a plugin or theme causes a fatal error on your site, and notifies you with this automated email.

In this case, WordPress caught an error with your theme, ButterBelly Pro Responsive Theme.

First, visit your website (https://www.beachfarminn.com/) and check for any visible issues. Next, visit the page where the error was caught (https://www.beachfarminn.com/wp-admin/themes.php?page=optionsframework) and check for any visible issues.

Please contact your host for assistance with investigating this issue further.

If your site appears broken and you can’t access your dashboard normally, WordPress now has a special “recovery mode”. This lets you safely login to your dashboard and investigate further.

https://www.beachfarminn.com/wp-login.php?action=enter_recovery_mode&rm_token=h7ekftrWFT9nhaDROvof5g&rm_key=YS49uik0LjZIvkge4PlSjD

To keep your site safe, this link will expire in 1 day. Don’t worry about that, though: a new link will be emailed to you if the error occurs again after it expires.

When seeking help with this issue, you may be asked for some of the following information:
WordPress version 5.4
Current theme: ButterBelly Pro Responsive Theme (version 1.0.2)
Current plugin: (version )
PHP version 7.0.33

Error Details
=============
An error of type E_ERROR was caused in line 846 of the file /home4/beachfar/public_html/wp-content/themes/butterbellytheme/functions/admin-interface.php. Error message: Uncaught Error: Call to undefined function ereg_replace() in /home4/beachfar/public_html/wp-content/themes/butterbellytheme/functions/admin-interface.php:846
Stack trace:
#0 /home4/beachfar/public_html/wp-content/themes/butterbellytheme/functions/admin-interface.php(100): inkthemes_optionsframework_machine(Array)
#1 /home4/beachfar/public_html/wp-includes/class-wp-hook.php(287): inkthemes_optionsframework_options_page(”)
#2 /home4/beachfar/public_html/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(”, Array)
#3 /home4/beachfar/public_html/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#4 /home4/beachfar/public_html/wp-admin/admin.php(254): do_action(‘appearance_page…’)
#5 /home4/beachfar/public_html/wp-admin/themes.php(10): require_once(‘/home4/beachfar…’)
#6 {main}
thrown

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