Maybe we could trade clogs. I just finished felting a pair and made the horrible mistake of answering the phone while the washing machine was doing my felting for me ... oops! They felted too long and now my ladies medium will fit a young girl about age 8 or 10
Ah well .. a nice sample to show prospective buyers!!!
If your clogs are still too large you might try more agitation. It's not the temperature of the water so much as it is the "tumbling"/turning/rubbing process. Hot-ish warm water will do the trick, a little soap (use a little dish soap, not laundry soap) and a lot of agitation. The more they agitate the quicker they felt.
However, if your clogs are fully felted and still too big then it's a matter of starting over with a sized down pattern. I've done that a few times with various test objects that I was so sure would felt down smaller than they actually did. A pair of boot liners quickly became Christmas stockings by the fireplace when they stayed large enough for a sasquatch's feet!