Remove background tool not available ?

I haven't been able to use the remove background feature for a while, at least a couple weeks. And looking over my images from around that time the feature wasn't working well. Which could definitely be the fault of my photos. But the reason I like capture so much is it could handle photos other programs can't 

even tho it reduces their quality a lot it luckily doesnt matter for what I do. Capture has been one my favorite resources for a few projects I make but now idk. Thank you !