Read counter reset

Hello,

Can someone tell me please if it is possible to reset the number of views counter when the customer’s role change ?

I explain my website functionnality : a customer buy the access to 1 article, he can display it only 5 times (5 views parametered for subscribers, and denied for the others). He is switched from user role to subscriber role.
After he reached his 5 views, his access is denied, and he is automatically switched to his precedent role.
It works fine, BUT : if he buy again the access to the same article, he can’t acceed to it, his counter is still on 5+ views…

That’s why I wonder if it is possible to reset the personal counter after a role switching.

Hope someone can help.