Deactivate online

Hi there, 

I have a problem.

my license had activated on computer A and B.

but, now I would like to activate on computer C. and I want to deactivate B.

But, the computer B had broken, can not power on, so, I can not to open the Rekordbox to deactivate.

So, is it possible to manage the license online like Serato.

Thank you