I was importing my data from Plytix and I received this error. Plytix is not familiar with this error so I’m wondering if this is something on the Shopify side. Thanks 
Hi @cclipson ,
Thank you for reaching out to the Community! I’m happy to provide some assistance with this request, to ensure it gets resolved. To confirm I’m fully understanding, is the app Plytix available within the Shopify App Store?
After taking a closer look, it seems that I wasn’t able to locate the Plytix app. Due to this, you will want to connect with the third-party app directly for further assistance with this error.
Their support team will be able to investigate this further and ensure it gets resolved as quickly as possible. For ease, I’ve gone ahead and included their Support Page for you to connect with!
In the meantime however, you can look into attempting a few of the local troubleshooting steps listed below to see if this helps to resolve. These steps include:
- Clear your Cache and Cookies.
- Access the shop in an Incognito Tab.
- Try accessing the shop from Another Browser (i.e Chrome, Firefox, or Safari).
- Try Another Device.
- Try Restarting your device.
- Make sure your device is Up To Date.
Please let me know if you have any other questions or concerns.