The cavity door does not stay in the centre of the guide ie is loose and when we try to close the privacy latch the door gets pushed and not aligned with the strike plate.
We have the following rollers that came with the cavity door
https://www.bunnings.com.au/hume-door-cavity-extra-trolley-kit-to-suit-evolution_p2035945
In another part of the house we have a better quality cavity door with better guide where the door sits and has no give more suited to having privacy lock.