Why can't I spot my own items?
Spotting is about other people finding things for you, so the platform stops you from spotting items on your own shared wantlist.
If you could spot your own wants, the spotting counts and leaderboards would be easy to game, and the "someone found it for you" notifications wouldn't mean anything. Keeping it to others' finds makes spotting genuinely helpful — and the leaderboards fair.
When you find your own want at a show, just buy it and log it like any other acquisition.