Fatal Error for trying to protect content on select pages.

I was reviewing a list of pages and marking specific ones that I want to protect.

I had "checked" about half dozen and it went into 'think mode' then came back with this.

Fatal error: Maximum execution time of 30 seconds exceeded in /home/content/91/7805491/html/wp-content/plugins/membership/app/rule/page/class-ms-rule-page-model.php on line 239

Please advise.