Deactivating causes ‘critical error’

I want to delete the plugin but when I try to deactivate the plugin I get the message "There has been a critical error on this website."

Can anyone help with this?

Thanks

An error of type E_ERROR was caused in line 161 of the file /home/admin/public_html/wp-content/plugins/wp-optimize/vendor/rosell-dk/webp-convert/src/Convert/Converters/ImageMagick.php. Error message: Uncaught Error: Call to undefined function WebPConvert\Convert\Converters\escapeshellarg() in /home/admin/public_html/wp-content/plugins/wp-optimize/vendor/rosell-dk/webp-convert/src/Convert/Converters/ImageMagick.php:161
Stack trace:
#0 /home/admin/public_html/wp-content/plugins/wp-optimize/vendor/rosell-dk/webp-convert/src/Convert/Converters/ImageMagick.php(252): WebPConvert\Convert\Converters\ImageMagick->createCommandLineOptions()
#1 /home/admin/public_html/wp-content/plugins/wp-optimize/vendor/rosell-dk/webp-convert/src/Convert/Converters/ConverterTraits/EncodingAutoTrait.php(57): WebPConvert\Convert\Converters\ImageMagick->doActualConvert()
#2 /home/sadmin/public_html/wp-content/plugins/wp-optimize/vendor/rosell-dk/webp-convert/src/Convert/Converters/ConverterTraits/EncodingAutoTrait.php(95): WebPConvert\Convert\Converters\ImageMagick->convertTwoAndSelectSmallest()
#3 /home/admin/public_html/wp-content/plugins/wp-optimize/vendor/rosell-dk/webp-convert/src/Convert/Converters/AbstractConverter.php(256): WebPConvert\Convert\Converters\ImageMagick->runActualConvert()
#4 /home/admin/public_html/wp-content/plugins/wp-optimize/vendor/rosell-dk/webp-convert/src/Convert/Converters/AbstractConverter.php(295): WebPConvert\Convert\Converters\AbstractConverter->doConvertImplementation()
#5 /home/admin/public_html/wp-content/plugins/wp-optimize/webp/class-wpo-webp-test-run.php(48): WebPConvert\Convert\Converters\AbstractConverter->doConvert()
#6 /home/admin/public_html/wp-content/plugins/wp-optimize/webp/class-wp-optimize-webp.php(56): WPO_WebP_Test_Run::get_converter_status()
#7 /home/admin/public_html/wp-content/plugins/wp-optimize/webp/class-wp-optimize-webp.php(20): WP_Optimize_WebP->set_converter_status()
#8 /home/admin/public_html/wp-content/plugins/wp-optimize/webp/class-wp-optimize-webp.php(44): WP_Optimize_WebP->__construct()
#9 /home/admin/public_html/wp-content/plugins/wp-optimize/wp-optimize.php(253): WP_Optimize_WebP::get_instance()
#10 /home/admin/public_html/wp-content/plugins/wp-optimize/wp-optimize.php(1791): WP_Optimize->get_webp_instance()
#11 /home/admin/public_html/wp-includes/class-wp-hook.php(308): wpo_deactivation_actions()
#12 /home/admin/public_html/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters()
#13 /home/admin/public_html/wp-includes/plugin.php(517): WP_Hook->do_action()
#14 /home/admin/public_html/wp-admin/includes/plugin.php(814): do_action()
#15 /home/admin/public_html/wp-admin/plugins.php(209): deactivate_plugins()
#16 {main}
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