Can I make Dollar Store dishwashing powder not terrible?

I made the mistake of buying dishwashing powder from the dollar store and it left a weird thick grainy film residue on all of our dishes. Is there a way I can add something to it or fix it so that it won’t do this? I’m being frugal and don’t want to waste the whole box even though it was only a dollar. Maybe I could add water to the mix and make it a liquid of sorts? Or use a vinegar rinse aid?