I get API error 26, when I send to x country, why?

This is because your account does not have coverage activated for that country. By default, international coverage is off on your account.

kwtSMS has international SMS coverage, but it must be enabled from within your account first.

To add coverage, Login to your account, goto Coverage and click Add. Then choose the destination country you would like to activate.

After you submit the request, our team will review it as soon as possible, usually, it will be processed same day.

Read more about international SMS rules.

Also, read our SMS API Implementation Best Practices for Developers to learn more on how to correctly build and protect your application.

Disclaimer:
By using international coverage, you acknowledge full responsibility for all traffic sent via your API and agree that kwtSMS is not liable for balance losses or message failures resulting from insufficient security measures or incorrect data formatting.

Activating international coverage significantly increases your exposure to automated bot abuse and fraud, risking the rapid drainage your account balance.