back to square one; ending up right back where one started
Idiomatic expression used when efforts or changes ultimately result in returning to the original, often undesirable, state. Conveys a sense of futility or irony.
I finally got promoted, but the departments merged and I'm right back where I started.
ダイエットに成功したが、リバウンドで元の木阿弥になった。
I succeeded in losing weight, but rebounded and ended up back at square one.