Fatal error – version 3.45.1

We recently upgraded to v3.45.1 of the plugin but have been experiencing the following fatal error on specific pages (that relate to a popular sports club management plugin sportspress):
[12-Feb-2020 05:17:56 UTC] PHP Fatal error: Uncaught TypeError: Argument 1 passed to MailPoet\Form\DisplayFormInWPContent::display() must be of the type string, null given, called in /home/stalban7/public_html/wp-includes/class-wp-hook.php on line 288 and defined in /home/stalban7/public_html/wp-content/plugins/mailpoet/lib/Form/DisplayFormInWPContent.php:26
Stack trace:
#0 /home/stalban7/public_html/wp-includes/class-wp-hook.php(288): MailPoet\Form\DisplayFormInWPContent->display(NULL)
#1 /home/stalban7/public_html/wp-includes/plugin.php(206): WP_Hook->apply_filters(NULL, Array)
#2 /home/stalban7/public_html/wp-includes/formatting.php(3802): apply_filters(‘the_content’, ”)
#3 /home/stalban7/public_html/wp-includes/class-wp-hook.php(288): wp_trim_excerpt(”, Object(WP_Post))
#4 /home/stalban7/public_html/wp-includes/plugin.php(206): WP_Hook->apply_filters(”, Array)
#5 /home/stalban7/public_html/wp-includes/post-template.php(425): apply_filters(‘get_the_excerpt’, ”, Object(WP_Post))
#6 /home/stalban7/public_html/wp-content/plugins/wordpress-seo/front in /home/stalban7/public_html/wp-content/plugins/mailpoet/lib/Form/DisplayFormInWPContent.php on line 26

We’ve de-activated MailPoet plugin to allow the rest of the site to work correctly – but appreciate any feedback on how to address the issue