That error could mean anything. It could be a problem with your website or with Printify. I also don’t know enough about Printify to say for certain what “send the consumer data” actually does.
So you may want to contact Printify about this. Their code is generating this error, so they should be able to say more about why you see it.
That said, please note that webhooks/callbacks from Printify to your website with us probably don’t work because of this security system. I can’t say for sure whether this is the reason for your issue (see above), but it might be.