theme unresponsive for mobile and error: Scrape key check failed

disappointed in this theme. bought it really expensive and it is a pain for my. very slow to load, very slow to comprehend and edit. tried to change functions.php file because it didn’t load mobile optimization and then it deleted every code in functions.php file. I tried to re-add it with code snippets and the problem persists . when adding I see this: Scrape key check failed