what's (someone's) beef (with someone or something)
What's wrong with someone? Why is someone upset? What is someone's problem? Wow, what's Cheryl's beef today? She's been really snippy with me all day. I'll tell you what my beef with you is: I'm really annoyed that you would leave all these dishes for me to clean up, instead of just doing them yourself! What's your beef with this project? You've had some issue with it from day one.