Dear Darshan
All of your settings seems to be correct my attention also went to point no.10 only as mentioned by Ajay Sir also but as you say you have done confirmation again but the situation is the same. Now please check following points also.
1 May be your production lot size or the activity quantities are too small hence the system is unable to calculate activity cost for Production Order. Ideally Costing Lot Size,Routing base quantity and order size should be the same to avoid calculation differences due to rounding.
2 Check production version used for Standard Cost and for Production order. Whether the two are same or different. If different the activities used in production version used for Production order are properly maintained and also check validity of those activities.
If even then it is not solved then please give screen shots of your activity master,KP26,routing and Cost analysis.
Regards
Rajneesh Saxena