harp on the same string 老调重弹；唱老调；翻来覆去

【例句】
Not to harp on the same string, I still insist that you go on with your study.
不是我老调重弹，我始终认为你应当继续你的学业。

I’ve already told you that I am broken myself. I wish you’d stop harping on the same string.
我已经告诉你了，我自己也分文不名，我希望你别老是老调重弹。