The inability to remember if you did something you do every day.
Every morning when you leave the house, you push the button on the garage door remote closing the garage door. Then 10 minutes later, you can’t recall if you closed the garage door because you do the exact same action at the exact same time every morning, so they all blend together and you couldn’t tell if your memory was from that morning or any of the previous mornings where you went through the same motions like you have countless times before. You just experienced Repetitive Familiarity Amnesia.