I got notified by copytrack that their client, YayImages, said I was using an image without permission and I should pay 350 euros. I got it from another stock photo dealer - it’s available at at least 3 I know of, including DepositPhotos - and proving this was very simple, but time consuming. I’m glad to see I’m not the only one. They’re hoping you didn’t save anything to prove you have the rights to the image and will just settle to make it go away.