This question was from a reader – How to congratulate on completion of Vrat? You don’t congratulate a person on completion of vrat but you bless them. The best way to do it by giving them the ashwirad or blessing that let their desire be fulfilled. Or you can simply say that all prayers on the completion of vrat and let there be peace and prosperity.
Whatever you wished to achieve through the vrat let it be fulfilled with the help of your personal deity or bhagvan. I will always remember when I pray.