>Sergey,
> I did not. I don't know how will need assistance here. I am more developer don't know much about administrative part.

Check this article How to troubleshoot performance problems in SQL Server

There is a section about locks in it.

select  
    request_session_id as spid,  
    resource_type as rt,   
    resource_database_id as rdb,  
    (case resource_type 
      WHEN 'OBJECT' then object_name(resource_associated_entity_id) 
      WHEN 'DATABASE' then ' ' 
      ELSE (select object_name(object_id)  
            from sys.partitions  
            where hobt_id=resource_associated_entity_id) 
    END) as objname,  
    resource_description as rd,   
    request_mode as rm,  
    request_status as rs 
from sys.dm_tran_locks