Q. If the Baal Tefilah benching Rosh Chodesh on Shabbat Mevarchim Adar HaRishon, made a mistake and did not say Adar HaRishon or actually did say so, but not as required Adar HaRishon, does he have to repeat?
A. Horav Shlomo Miller’s Shlit’a opinion is that if possible he should repeat, since it may be essential to say it correctly as when writing a Kesuba or a Get (See Kav Naki (105: 16).