So the premise is: they travel back in time, change their future, travel back to the present, forget everything they did while time traveling, and now have to just experience their new future without knowing anything changed? Do I have a that right?
I mean, how do you know this isn’t the backstory for every character in every story ever? How do you know you didn’t JUST do this yourself?
Ahh, yeah, I think I didn’t quite follow OP’s request. The part they don’t remember is the time between where they traveled to in the past and their “present”, and the story is about them intuiting what happened in there.
From the title it sounded like the protagonist was suffering amnesia-like symptoms about how the world used to be along with everyone else.