From the homescreen of the Localhost App:
Tap the “Buy time” button below the time balance.
Select the amount of time you would like to add to your account balance.
Tap “Purchase pass”
Your account balance will update to reflect the purchased time. A receipt will be sent to the email address associated with your account.
Heads up!: Your play time balance is different at each localhost location. Before adding time to your account balance, make sure you’ve selected the correct Localhost Venue.