Unfortunately, there isn’t going to be anything simple I can tell you to make it work again. It sounds like you have an infinite loop condition. All I can to is make guesses that I cannot test.
The first thing I would do is to see if it has something to do with the formatting of the value. Replace your line of code with
<?php the_field('shop_the_look_code', false, false); ?>
what that will do is bypass all of the formatting of that field value so that you can eliminate it as a cause or determine that formatting is the issue.
