Updating the plugin breaks the site

Hi, I’m currently stuck with the version Version 1.10.1 which I’ve never been able to update to the latest version. I tried upgrading from each version until the newest one but the 1.10.1 is the latest version before the fatal error appears and breaks the whole site. Here’s the error log after updating the plugin to the latest version.

[05-Jan-2021 20:36:54 UTC] PHP Fatal error:  Uncaught Error: Class 'PUM_Install' not found in /home/genealog/public_html/sglevis/wp-content/plugins/popup1.10.1/popup-maker.php:362
Stack trace:
#0 /home/genealog/public_html/sglevis/wp-includes/class-wp-hook.php(287): pum_init('')
#1 /home/genealog/public_html/sglevis/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array)
#2 /home/genealog/public_html/sglevis/wp-includes/plugin.php(484): WP_Hook->do_action(Array)
#3 /home/genealog/public_html/sglevis/wp-settings.php(420): do_action('plugins_loaded')
#4 /home/genealog/public_html/sglevis/wp-config.php(91): require_once('/home/genealog/...')
#5 /home/genealog/public_html/sglevis/wp-load.php(37): require_once('/home/genealog/...')
#6 /home/genealog/public_html/sglevis/wp-blog-header.php(13): require_once('/home/genealog/...')
#7 /home/genealog/public_html/sglevis/index.php(17): require('/home/genealog/...')
#8 {main}
  thrown in /home/genealog/public_html/sglevis/wp-content/plugins/popup1.10.1/popup-maker.php on line 362

Thanks for helping me.

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