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Is it one with a rod that you push down on or is it a sprung one?
In any case - try removing the trap from underneath the basin and then you can poke a pencil/screwdriver up from underneath it may help you free it off.
If not, remove the large nut from underneath and push the whole waste fitting up and out and replace it with a new one.
If it’s a pedestal it may be tricky, especially if it’s been tiled around.
If it’s a vanity unit it should be a lot quicker/easier/cheaper.
Hi IND_Nick,Sometimes you can unscrew the chrome plug from above which gives you access to the pop up mechanism from above. Try turning it counter clockwise and see if it comes loose.
Reply to the thread, titled "push plug stuck" which is posted in Bathroom Advice on Plumbers Forums.
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