Without the correct format and country prefix, the destination may be recognized differently from what you intend them to be. For instance, within the UK, numbers should start with a 0, but when calling or texting the number in the international format, the international prefix (44) must be added, and the leading 0 removed. The correct format for this number would be +447512345678.
If you deliver a phone number that is not formatted correctly, tyntec will reject the request and you will receive an error code. You will not be charged for this attempt. If you’re not sure if the phone number is still active or valid, verify the phone number status with tyntec’s Number Verification API.