According to Cambridge dictionary 'loose end' means 'something that still needs to be done or explained.' I was chatting with Facebook support about a problem with my account and when the person asked if I need help with anything else, I said "Hold on a sec. I want to send you a screenshot of the problem. I don't want any loose ends this time."
I said that because I talked with them about the same issue twice before. And this time I wanted to make sure that I let them know about the problem in as much detail as possible. So I thought the idiom would fit here even though I wasn't sure if it would.
Also while looking it up I came across 'tie up loose ends.' Say I'm doing a project and someone asks whether it's complete. Can I say "Almost. I just need to tie up some loose ends and I'll be done."