Hey! Welcome to Sandbox.
We understand that at times your API calls may exceed your monthly API quota which may result in production downtimes. To avoid this in a timely manner, Sandbox allows you to go over and beyond your quota, which is known as an Overdraft. You can turn it on or off based on your requirements.
However, for every call made after exceeding the quota, you will be charged on a pro-rata basis as per your subscription plan. The invoice for the overdraft usage of the quota will be generated at the end of the billing cycle.
The registered mail id will get notified when the consumed quota exceeds 50%, 90%, and 100% of your monthly quota. You can notify your team members by configuring postback notifications when your subscription is going into an overdraft. Alternatively, you can upgrade your subscription to avoid overdraft billing.
Head over to the Overdraft Tab and enable overdraft.
If overdraft has not been configured, you will get the following alert in your subscription page.