PayPal order confirmed and after a minute status change in deleted

[Nicola1008]

Hi,
I have a problem with PayPal in a couple on my site.

Users of my sites make a purchase, pay correctly and PayPal changes the status of the order to confirm. Sometimes, however, one minute after the order PayPal changes the status again and cancels it, without anyone having canceled the order.

Anyone can help me? It is a big problem! Thanks!

[jenkinhill]

Which versions of VM & Joomla?  Which PayPal payment method?