OpenCart, PayPal processing, and SOS Inventory

Hello -

We are using OpenCart for our store however we are using PayPal for the processing. I am trying to integrate SOS inventory with QuickBooks Online. The SOS inventory instructions give a URL to provide for PayPal but it seems OpenCart is intercepting that feed so it never gets back to SOS inventory. Can anyone provide suggestions or guidance on what to do to send the feed to SOS inventory?

You should have to go Opencart QuickBooks Integration which have to Custom, not Plugin or Add-ons or ready software.