Class ‘WBCR\Factory_Templates_102\Impressive’ not found in /www/

Hi, getting this following error in admin email, and the plugin version is 1.5.5
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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 one of your plugins, Robin image optimizer.

First, visit your website and check for any visible issues. Next, visit the page where the error was caught (https://**site link**/wp-cron.php?doing_wp_cron=1635482348.3441040515899658203125) 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.

**login link***

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 5.8.1
Current theme: Beaver Builder Child Theme (version 1.0)
Current plugin: Robin image optimizer (version 1.5.5)
PHP version 7.3.28-1+ubuntu16.04.1+deb.sury.org+1

Error Details
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An error of type E_ERROR was caused in line 21 of the file /www/wp-content/plugins/robin-image-optimizer/admin/pages/class-rio-page.php. Error message: Uncaught Error: Class ‘WBCR\Factory_Templates_102\Impressive’ not found in /www/wp-content/plugins/robin-image-optimizer/admin/pages/class-rio-page.php:21
Stack trace:
#0 /www/wp-content/plugins/robin-image-optimizer/includes/class-rio-plugin.php(182): require_once()
#1 /www/wp-content/plugins/robin-image-optimizer/includes/class-rio-plugin.php(118): WRIO_Plugin->registerPages()
#2 /www/wp-includes/class-wp-hook.php(303): WRIO_Plugin->pluginsLoaded(”)
#3 /www/wp-includes/class-wp-hook.php(327): WP_Hook->apply_filters(NULL, Array)
#4 /www/wp-includes/plugin.php(470): WP_Hook->do_action(Array)
#5 /www/wp-settings.php(444): do_action(‘plugins_loaded’)
#6 /www/wp-config.php(91): require_once(‘/www/wp-setting…’)
#7 /www/wp-load.php(50): require_once(‘/www/wp-config….’)
#8 /www/wp-cron.php(44): require_once(‘/www/wp-load.ph…’)
#9 {main}
thrown

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