I would just let them be for a week with no feeding attempts. Trying over and over seems to stress out my snake.
My snake was fed live and switching was easy. The weird part is she will NOT eat a wet rat. It has to be dry... So I warm them up in a ziplock bag. Also to see if she'll eat I get the frozen rat and wave it around the tank and if she pokes her head out then I go thaw it.