Hello there! I'm sorry to hear that you lost your starter. How did you lose it? We also can't reset players accounts, so hopefully we can find a way to somehow find your Starter.
I suggest you try to get in contact with a Manager, as they might be able to help. If they are nowhere in your PC or Party and you've tried relogging, I'd definitely go to a Manager. You could also try to do /fixinv to see if that helps.