a hard time
1. Grief or frustration intentionally inflicted on one by another, in the form of teasing, bullying, or other ill treatment. The school bully started giving the new kid a hard time until the teacher sent him to the principal's office.
2. Difficulty or a source of struggle. Often used in the phrase "have a hard time." I'm really having a hard time in math this semester—I need to get a tutor.
*a hard time
and *a bad time; *a rough timetrouble [over something]; unnecessary difficulty. (*Typically: have ~ give someone ∼.) Please don't give me a hard time. The clerk got a hard time from the boss, so he quit.