Contract lines are not getting expired

 Hi 

We have multiple instances for our poject like Sandbox, Staging and Live. They are behaving differently on Contract lines.

In staging on the contract line end date, the lines are getting expired.

But this is not happening in Sandbox and live, what might be the reason?

And we observed that on the contract lines in Staging  the 

Total Cases/Minutes is setting to 1 on expiring but this is not happening in PROD and Sandbox. And if we are manually placing it in there it is reseting it to ZERO.

Can any one say why this is happening..?

Thanks