Can't change header image in GB or WP, using the "Service" pre-made site

Hi there,

Much like the title says, I can't find how to change the header image in any non-home page for the "Service" pre-made site (made with GenerateBlocks). I can't find any option in either the Wordpress Editor (which I believe is only really being used for the menus?) or the GenerateBlocks editor. I changed the home page image fairly easily, but it looks like there's no equivalent block where there should be for any other page. I'm completely new at this, thank you for your time. I attached a link, I'm wanting to change that top image with the blue gradient for example.

Thank you,
Matthew