One of the first things I worked hard to find out was which spelling was in fact best to use for my role. As a Samoan child, I have heard - used and been acknowledged as a person of the Pasefika (spelling from the Samaon and Tokelauan culture). In looking across different organisations who work within our Pacific communities, speaking with Pasefika leaders and educators it confirmed my understanding that Pasifika and Pasefika are both commonly used to refer to Pacific people, culture, and languages. The spelling difference is due to pronunciation across different Pacific Island languages. In New Zealand, 'Pasifika' is the more widely used term.
The choice of which term to use may depend on context and personal preference. Some great advice from an mentor Aunt (Human Rights Advisor- Pasifika at the Human Rights Commission) it is important to be aware of both spellings and to use them respectfully when working with Pacific people and communities. My mother's answer, "O le mea a e tasi, Pasefika - Pasifika - Pacific". It is the one, it is the same.