Custom code for "Price on request"

hi all 

I have a Squarespace site created last year, where I am using the commerce functions to have a "webshop" where I can show used products I have for sale. Some products are difficult to set a price for, so I want to have the price say "price on request" if the price is 0 in the inventory management. Ever since the creation, I have had the following custom code injection to automatically change prices that are 0 to "Price on request". For some reason this has now stopped working. I'm not sure exactly when. 

Any thoughts on why it doesn't work?

Thanks in advance