If you do not make a payment by choosing the "Extend Validity" option before the Validity expiry date (mentioned on the Top right in your account), your entire existing balance will be invalidated. Which also means your service will be suspended , Calls and SMSes through Exotel will be terminated.

However, if you do make a validity payment before expiry, we will carry forward your entire current balance to the next validity period so that you can use it later.

We'd be really sad to invalidate your balance and would love it if you can make full use of this balance before that.