That's partially correct. The first 2 referendums were lost by a few %, and the last was boycotted since it was held during the pandemic and when Kanaks asked to delay it since it would disproportionately affect them, France refused. France will do anything not to lose the territory, since it's strategically important to them.
The whole point of the new voting law they are protesting is that any subsequent vote would be stacked in France's favor, since local population is already diluted to around 50%.