Can't generate stems

On some songs I can generate stems but on this one I'm trying, it just spins forever, and worse still is that when I cancel/close and try again it charges me MORE credits. It should already see that I've tried to generate stems on this song and not double-charge. It's been draining my credits every time I attempt it. I've emailed suno support but that usually takes 3 months to get a reply so I thought I'd try here. :)