This is a classic! It is either one of two things. Either your child really didn’t hear you, or she just lied to try to make the reason she didn’t follow instructions look like your fault instead of hers.
If you are constantly hearing this excuse for instructions not being followed, then you should first ask yourself, “Did I make eye contact with my child when I gave the instruction?’ If you have a habit of yelling instructions through the house, then you have no way of knowing if the child really did hear you or not. I would have a child come to you first, then give an instruction. This is what I do to make sure I only have to give instructions once, thus more effectively teach my child to follow instructions.