Frankly, I don’t see WHY you would need login access for that.
My question is simple: how do I change the contact form background image?
1. I know where this image is and I can change it myself and I already did so. The problem here is with updates: every time I’ll update I’ll need to change it back.
2. In customizer there is an option for that but it doesn’t work.
3. Is there a way to include it in a child theme?