Helpdeskz API issue

I am experiencing an issue with the Helpdeskz API, specifically with creating users and tickets using PHP. I have the necessary API credentials and documentation. I need assistance in troubleshooting and resolving this issue.

Ideal skills and experience needed for this project include:
- Experience with Helpdeskz API
- Experience with Codeigniter
- Proficiency in PHP programming language
- Knowledge of API authentication and data retrieval
- Strong problem-solving and troubleshooting skills