Sridhar
Can you check your ZPRS Condition type or share the Settings of ZPRS in Pricing Procedure as well as for Condition type.It seems that due to ZPRS condition it is inactivating your ZPRO condition.
Can you remove ZPRS Condition type from Sales order and check in Sandbox environment - just to confirm.
Share business logic behind Condition type ZPRS to help you better.
Regards
Amit
