The biggest choke I personally remember was three putting to shoot 70 in a qualifier for my club championship the summer between high school and college. I was in the 0-1 handicap range at the time but I've never broken 70.
I remembered that for a while because after going to college I stopped playing as much and for a long time I figured I'd blown every chance I had to break 70. I had shot 70 even 3 times. Recently (since ~2020) I've been playing more again and gotten back down to a 3, so I might have a shot to do it eventually. I've put together another 70 and a couple of 71s so hopefully I can manage it eventually.