Different Durations for Activities & WBS

Hello EVerybody,

Hope everybody were doing well.

I have a small complexicity while doing a schedule. When some activities entered under a WBS with proper durations and relationships.

But after scheduling, I found the WBS durations are less than the project durations and i have checked the calenders that i assigned for activities & projects and even WBS also.But still the problem is same.

Can any body will suggest to get out of this problem and the calender i have given is 7 days working with 8hrs/day 

Regards,

Ashik