You can change your Volnyn package from your account billing area. Upgrades usually apply right away; downgrades take effect at the end of the current billing period so you keep access you already paid for.
Upgrade
Go to your profile / billing page, choose a higher package, and confirm payment. Extra credits or features unlock after the charge succeeds.
Downgrade
Select a lower package and confirm. You keep the current plan until the period ends, then the lower plan starts automatically.
Still need help?
Open Get help in your account menu, or submit a request from /user/support while signed in.