Welcome to the Bunnings Workshop community. Thank you so much for joining us and sharing your question about how to fix peeling paint from your ceiling.
There is always an underlying cause as to why ceiling paint peels off from your ceiling. I suggest getting a ladder to test if the ceiling gib panel has gone soft. Push the peeled area with your finger and see if the panel is soft. If it is, odds are there is currently a leak coming from your roof and water is settling in that part of your ceiling. the leak must be repaired before you fix the ceiling paint.