Get Related Contacts with Accounts as Parent Module 500 Error

Get Related Contacts with Accounts as Parent Module 500 Error

Ran into a new problem this morning.  Here's my API call:

"https://crm.zoho.com/crm/private/xml/Contacts/getRelatedRecords?newFormat=2&apikey=$apikey&ticket=$apiticket&parentModule=Accounts&id=$related)", "r") or exit("Unable to open file!");

This is throwing a 500 error.  I've echoed my variables, and they are correct.

Is there something wrong with my syntax here?