be rushed off (one's) feet
To be exceptionally busy, especially to an exhausting or exasperating degree; to be made to work very hard and very quickly. We have three parties of 40 scheduled for the dining room this evening, so all of our servers are going to be rushed off their feet. With three young kids, it's hard to remember a time when I wasn't rushed off my feet.
rushed off your feet
BRITISHIf you are rushed off your feet, you are very busy. Now we have fewer staff in this department, I'm rushed off my feet. You've been rushed off your feet all day, but what have you actually achieved?
be/get ˌrun/ˌrushed off your ˈfeet
be very busy: In the last few days before the holidays, the sales assistants were rushed off their feet.