When you create an account in the Sinch Customer Dashboard, it is created as a Trial account. Trial accounts allow you to try out Sinch products and services, but they have certain limitations:
To overcome these restrictions, you can easily upgrade your account:
Log in to the Sinch Customer Dashboard and select the Upgrade option from the Billing menu on the left panel. The Upgrade page is displayed:
This page allows you to select your payment method and choose how much you would like to add to your account. You can choose to pay by Credit Card or PayPal.
When upgrading your account you must pay in a minimum of 10 units of your account currency, for example, $10 USD for US based accounts.
Follow the on-screen instructions to select your payment method and add funds.