You can't change your choice after you choose in nameless event. Because the choice you choose has been save into persistent file not in save file. If you want to re-choose again, you need to have a previous persistent file (one before you choose a choice.)
You didn't understand what I was saying. I DIDN'T pick anything yet. I saved, went to meet him and pick and it acted like I already did and reset to try again. I didn't reset, I didn't pick, I just saved before doing the event for the first time and it Acted like I already had. I wanted to know if there is a way to know which choice I apparently did.