tap head

The hot one has been leaking for a while. Can someone please help me figure out how to change the washer on this one? I can't figure put how to gain access. Thanks!

I have beautiful Pegler Biarritz crosstop taps but one tap has started to spin and not turn on/off the water. I can pull the tap head off and can see that it is attached to a plastic corrugated spindle. Inside the tap head the plastic corrugated sheath that attaches to the spindle is no longer...