Bride Wars (2009) on Netflix

In Manhattan, the lawyer Liv and the school teacher Emma have been best friends since their childhood. They both are proposed to by their boyfriends on the same day and they plan their wedding parties in Plaza Hotel, using the services of the famous Marion St. Claire. However, due to Marion's secretary's mistake, their weddings are scheduled for the same day. None of them agrees to change the date and they become enemies, trying to sabotage the wedding party of the rival.