Theme Customize not working

For some reason when I click the “Customize” button for the Blocksy it drops to an error page with the following error.

Fatal error: Allowed memory size of 41943040 bytes exhausted (tried to allocate 32768 bytes) in /home/seakingb/public_html/wp-admin/includes/template.php on line 1885
There has been a critical error on this website. Please check your site admin email inbox for instructions.

All was working fine then all of sudden it’s not. I’ve tried removing the them and reinstalling it but it keeps doing it.

No other them does this, so until I find a fix I’m going to need to find a fix.