have no business (doing something)
To have no legitimate reason, experience, or authority to do something. Mom, you had no business eavesdropping on my phone call like that! He has no business running this meeting—he has no idea what this project entails.
have no business doing something
to be wrong to do something; to be extremely unwise to do something. You have no business bursting in on me like that! You have no business spending money like that!