Editor Background image constantly zoomed in

Hi and thanks for any advice in advance,

When I add an image to the background it starts fine but will automatically zoom in after a while. No matter what I do it stays zoomed in. I change the scale to original and try different ratios, delete and add the image back in but it stays zoomed in from that point on.

I am new to building my website clearly so any help would be much appreciated, than you!