Yes I did
According to the task these are the inputs I have provided
Under Properties tab
Username: The username I have created for myself under Clickatell as login account
Password: The password for my Clickatell Login account.
Recipient: the mobiled number prefixed with the country code
Service: Clickatell
SMS Type: Standard
Delay: <blank>
Sencer: <blank>
Text: Hi
Under Provider Paramenters:
Name: api_id : the value which was created when I selected the SMTP API under Connections in the Clickatell website.
After providing all these values I clicked on the Test botton and the same Authentication Failure Error poped up.