Appointments+ Redirect

When I use the code in the FAQ to redirect my users to a thank you page I get an error that I'm not familiar with. I've copied the code directly into the functions.php of my child them. When I add it I get the error "Parse error: syntax error, unexpected T_FUNCTION" on the first line of code: function app_redirect( $script ){

Some things:
- I'm using a child theme (no other issues with using the functions.php file there other than this one)
- V 1.2.5 of A+

Not sure if there's any other relevant info