Yes, unless the use of Artificial Intelligence (AI) has been explicitly allowed in your assessment task, using AI to complete your assignment may be a form of contract cheating and is plagiarism under University policy.
However, it may be acceptable to use AI when asking questions as a starting point for how to approach an assessment task. Yet the information that AI provides is not always reliable, so it is important to do your own research and to write up your assignment using your own words.