You can upgrade, downgrade or cancel your plan from your online Tello account or using the free "My Tello" app (Android version).
Log into your online Tello account
and you will arrive on the "My Tello" - "Dashboard" page.
There you will see the "My Plan" box with options to either Change or Cancel your plan.
The "Change Plan" button will provide you with the option to either upgrade or downgrade your plan where available.
Upgrading or downgrading your plan will immediately replace your existing plan with the new one selected and your new billing cycle will start immediately.
You will be charged today for the new plan once you complete the checkout process and the newly configured plan will be active from that very moment.
There is no option to change your plan today to take effect on the next billing cycle.
You will be charged today for the new plan and renewal will be in 30 days' time.
If you want a new plan to take effect toward the end of this billing cycle, you need to change your plan yourself at least 24 hours before your next due billing date.
Any remaining balance (minutes, data) from a service you are renewing will roll over the following 30 days.
Any remaining balance from a service you are excluding from the new plan will expire on the original expiration date.
The "Cancel Plan" button allows you to cancel the automatic billing & renewal of your plan.
If you cancel your phone plan your remaining balance will remain valid until the end of the current billing cycle.