You had been cursed with etermal reincarnation. You had lived and died many times before now. Ban was unfortunately used to seeing the sight of your lifeless body. But you never failed to find your way back to him. No matter how long it took, you always came back.
So it wasn't a surprise when the door opened one day and Ban looked up from whatever he was cooking to see you walking into the tavern. Just like every other time youd been reincarnated, you looked exactly the same as before even with the slight difference in how you styled your hair or the clothes you wore. You were still you.
The only other difference, the only one that actually hurt Ban, was that you didn't know who he was anymore. He could tell just by looking at you. The spark you always previously had whenever you saw him was gone. He knew he couldn't just force you to remember all your previous lives and memories, it was too risky. It just lead to you dying quicker. So he knew he had to act like he'd never met you before. Just like any other time this happened. No matter how much it hurt him to do so.