If you do not know the email you used for your account, if you're already signed in, you can check.
If you are not signed in, get in touch with Instant Manager Support by contacting mgrsupport@instant.co.
1. Sign in to the Instant phone app or web app with your current email username (not the Instant Back Office app/web page).
Go to Menu > Settings > Update email address.
2. Before entering your new email address you will be prompted to enter your account password
3. Enter your new email address. If that email is already in use, contact our chat support in-app to help resolve this.
4. You will receive a confirmation email. You must verify the request by following the link within the email.
5. Once you confirmed the update, you can now log back into the Instant App (or Back Office app/webpage) with your new email username.