If a person mistakenly said v’sein tal u’mattar in the summer:
- if he didn’t yet say the shem HaShem at the conclusion of the berachah, he should go back to the beginning of the berachah.
- if he said the shem HaShem only, he should say lamdeinee chukechoh, and then go back to the beginning of the berachah
- if he said further, he goes back to bareich aleinu and repeats from there and on.
if he said the yiheyu l’ratzon that he says at the very end of his shemoneh essraiy, he repeats shemoneh essraiy—even if he did not yet take the 3 steps back.