PARQUET Floor Stain ... can't get it out!

Try baking soda (bicarbonate of soda) first, mixed into a paste with water. Is the stain in a very visible place? Diluted vinegar or lemon juice might shift it.

Try with some nailpaint remover, ca

It should be nailvarnish remover , be carefull in the beginning watch if the stain doesn't go deeper.

cloth over stain, hot iron--not too hot. keep iron moving and it will remove the moisture. Have done this a million times to get rings and other stains out of wood--dinning table and wood floors. good luck