Activations problem

 
I bought a product that has 5 activation was installed and working properly on all three computers then suddenly one of the computer is asking for new activation while others are still active and were activated the same day. What has gone wrong and how can it be fixed?
Productivity - USA - MetaTrader 5 Help
Productivity - USA - MetaTrader 5 Help
  • www.metatrader5.com
The productivity index measures the output produced for each hour of labor worked. This indicator is useful for predicting inflation and output...
 
Seems, the Windows on one computer was updated, and the one activation was lost because of that.
It is the well-known situation. You need to delete the product from Metatrader, and install it once again (and yes, one actication will be lost because of that as you mentioned above).
It is very well-known situation.