I have an operation which is executed every minute for years and once I had this:

"There is already an open DataReader associated with this Command which must be closed first."

This is the SQL that generated it:

DECLARE @Numero Integer

SET @Numero=1

SELECT Robot.NoServer,Robot.Run FROM Robot (NOLOCK) WHERE Robot.Numero=@Numero 

I am not sure if this could have been related to a network issue. This has happened a few months ago and I am only making a checkup on this today. When a SQL command generates this error, could it be related to such a situation?