expression
please don't fuss over me; don't go to any trouble; don't bother
A polite set phrase used when declining someone's offer of hospitality or assistance, often said to a host or someone who is about to do something for you. It conveys 'please don't go out of your way for me'.
お茶でもいかがですか？—いえ、お構いなく。
Would you like some tea? — No, please don't bother.
どうぞお構いなく。すぐ帰りますので。
Please don't go to any trouble. I'll be leaving soon.