To make using our service simpler, we’re streamlining the options to test sending SMS. Up to this point, you could decide to use the parameter `debug` or a testing environment (sandbox) to test our service without actually sending a message. Since these are two ways to use a function that is essentially the same, we decided to remove one of those options. **We are deactivating the `debug` parameter on 12 December 2023**. From this point onward, please use the sandbox as a testing environment. **!!! Messages sent in live environments using the `debug=1 ` parameter will be sent and charged! !!!** To use the sandbox environment, [create a sandbox API Key](https://help.seven.io/en/testenvironment-sandbox) and use this for testing.