Liquify tool error " The Backdrop settings are preventing the preview from showing image changes"

Hi there, I'm using photoshop 2021 on Windows 10 and I cannot see a preview of the image I wan to work on in liquify. I have tried toggling show image, show guidelines, show backdrop, changing layers in backdrop, moving the mode to in front, behind and blend, but still no image preview. If I click in the working window I get a background settings error message. Does anyone have any advice?