наступить дважды на одни и те же грабли (nastupitʹ dvazhdy na odni i te zhe grabli)

Literally: To step twice on the same rake

Example: “Он снова одолжил деньги тому же человеку: наступил дважды на одни и те же грабли.” — He lent money to the same man again, making the same mistake twice.

Origin: Stepping on a rake makes the handle fly up and smack you in the face, a classic slapstick image. Stepping on the same rake twice is making the same mistake again without learning from it. The phrase is modern colloquial Russian, recorded in Kuzmich's dictionary of popular phraseology (2000); its first use is not documented.