If you exhaust your data before the end of your 30-day period, you can still make calls and send texts until your plan renews.
If you require more data, you have two choices:
Purchase a booster: This add-on provides extra benefits alongside your current plan and expires with your plan's duration (subject to availability).
Buy a new plan: Opt for a plan without the 'booster' feature.
Select the option that aligns best with your needs.