How to fix below blocking problem on SQL server 2014
As stated by a previous user the lock type indicates that your query tries to acquire an Exclusive lock on a resource.
Is your predicate (Col1=@col1) supported by in index ?
Some options for a query referencing a specific table to acquire locks on other tables can be: triggers, fks and fk cascading.
More info is required. See this post for more ideas.
Have you tried to capture the blocked process report ?
See this post for how to run a server side trace to capture the &quot;Blocked Process Report Event&quot; constantly in the background so that when your issue occurs you do not miss it and have the data needed for analysis