Unable to communicate back with site to check for fatal errors, so the PHP change was reverted. You will need to upload your PHP file change by some other means, such as by using SFTP

Hi @thetraininglady

I found a StackOverflow thread here regarding the same error. A lot of users were reporting it was caused by a plugin conflict. Have you tried disabling plugins to see if that allows you to proceed?

As a workaround, have you tried editing the files manually using a text editor versus the native Theme Editor?