You don't have anything to worry about. Let's recover it.
1. Check if you have added the correct email. The e-mail was given to you when the onboarding started.
2. Double-check if there are no blank spaces in your username. It happens to the best of us, that's ok.
3. If even after the steps above you don't remember, or there is an error, contact the Kitch support team - email@example.com.