Thread Subscriptions Deletion Fails

I tried to delete some of the thread subscriptions in my User CP
but if I select the delete en select 1 or more subscriptions.... and clicj Go.
No subscription disapears!

I suspect I'm doing something very simple very stupid but I can't figur out how to get them removed.

Thx in advance.

It's a known problem on this forum and one we haven't been able to track down and correct. We hope the next upgrade will fix it.