How do I unplug this plug?

[OM2]

I've got 2 plugs that I don't know how to unplug!!

See below for a picture:

I've unplugged it before!
But I just cant remember what I did!

To plug, you press the middle button

To unplug...??
I thought it would be to again press the middle button - and up it would pop back up!
But, no - this doesn't work!

Downstairs sink plugged. After messing around with it for 5 min, I went upstairs to test on the one there - erm... that one's now plugged as well and I cant unplug!

HELP!!

Thanks


OM

 

[Alarm]

No "rods" by the taps,or below?

 

[kevindgas]

normally as you said press to plug, press again to unplug

 

[cajar]

got a magnet?

 

[cantaloup63]

How about a car valve grinding rubber sucker thing ?

 

[foxhole]

Take off trap and push up from below, may need a clean or replacement if spring has failed.