RuntimeException not namespace properly - throws class not found error

[wallyhall]

There are references to throw RuntimeException(...) when curl calls fail, but the class is a PHP standard and is namespace outside the project.

There's a use Exception at the start of the file, but RuntimeException isn't resolvable via that.

[wallyhall]

See example fix in pull request #24

[Parvindersib]

Hello @wallyhall

Thank you for contacting us.
We appreciate your suggestions and merged the PR.

Regards
SendinBlue Team