Yes, the ticket system is probably the right way.
My account was also blocked for uploading because I uploaded silhouettes that were supposedly created by AI, at least that was IStock's opinion.
After a somewhat lengthy communication with the ticket system, during which I had to control myself to remain particularly friendly and of course humble, I am now allowed to upload 50 images per week again. And no, they weren't AI images that I had uploaded, but if their automatic system says this is AI, that's probably their reality.
In the end, this stamping fits in with IStock's 15% share policy.