have enough on (one's) plate
To be sufficiently busy or preoccupied with work, problems, or difficulties as to be unable or unwilling to cope with anything more. I really wish I could help you move this weekend, but I have enough on my plate as it is!
have enough on your plate
or have a lot on your plate
COMMON If you have enough on your plate or have a lot on your plate, you have a lot of work to do or a lot of things to deal with. I'm sorry to bother you with it, Mark, but John's got enough on his plate. I have a lot on my plate over the next year with the Olympics coming up. Note: You can also say that someone has their plate full or has a full plate. I'm making no promises. My staff have their plate full at the present time.