Panerai Crown Unwound Suddenly?

[kestorr]

Hi gurus of this forum.

Would like to seek your kind advice. Was winding my Pam000 as usual today. Was midway winding it (not nearing the end), when suddenly the crown started to unwound itself and spun freely anti-clockwise.

Tried winding it back again to the end, everything acted normally as it should.

What is the hell is going on? I shook the watch but couldn't hear any loose parts i.e. just in case something broke.

Any kind souls can advise me? Thanks in advance.