When dealing with restrictive Vs non-restrictive commas, you need to consider whether the additional clause or appositive is narrowing down the possibilities for the item you're talking about (no comma) or if adding that information doesn't help you narrow down who you're talking about.
E.g. compare and contrast the following restrictive and non-restrictive clauses:
The children who are nice get a reward. (No comma in this restrictive clause means that there is a larger group of children, a subset of whom are nice; the detail of being 'nice' narrows down the scope of 'children'.
The children, who are nice, get a reward. (Commas being used here implies that all of the children are nice, so adding the detail of being 'nice' doesn't narrow down whom you are talking about.
Same with appositives:
Restrictive phrasing:
She appeared in a pivotal role in her film Star.
('Star' narrows you down to just one of her films)
Non-restrictive phrasing:
She appeared in a pivotal role in her previous film, Star.
('Previous film' specifies the exact film, so adding that the name of the film is 'Star' doesnt do any further restricting).
TL;DR: it's non-restrictive here, so use a comma