I ran sp_who2 and also checked in activity monitor, there are no blkby sessions.

I ran below query. No output.

select * from sys.dm_exec_requests

cross apply sys.dm_exec_sql_text(sql_handle)

cross apply sys.dm_exec_query_plan(plan_handle)

where session_id = 63

Looks like no blocked process now. Is sql server resolves this automatically. How to find what caused the problem. Thnaks!