This relates to older clubs setting up a BoosterBucks fundraiser or sell QR code Tickets in the Store for the first time. An additional merchant account is needed for these features. Newer clubs automatically sign up for two when launching your BoosterHub. You can check your existing merchant account in Settings > Boosterhub Settings.

If you don't finish the application for the additional merchant account, it will expire in 90 days. You can complete it anytime if you decide to use BoosterBucks fundraising or BoosterSTUB QR-code Tickets in the future.