SQL Server 2012 Error 22022


 Hi,
 
I am getting Error 22022 while running job from SQL Agent. Job contains maintenance plan for taking database backups. backups are not done from last 3 days. but the second part of maintenance plan, for log backups is running fine i.e  happening every hour. Below is the error i get once i restart the sql agent and run the job manually

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Start failed for Job 'B01-BI Databases Backup.Full'.  (Microsoft.SqlServer.Smo)

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Program Location:

   at Microsoft.SqlServer.Management.Smo.Agent.Job.Start()
   at Microsoft.SqlServer.Management.SqlManagerUI.StartAgentJobs.StartJobAction.DoAction(ProgressItemCollection actions, Int32 index)
   at Microsoft.SqlServer.Management.SqlStudio.Controls.ProgressItemCollection.DoWorkOnThread()

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An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)

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Program Location:

   at Microsoft.SqlServer.Management.Common.ServerConnection.ExecuteNonQuery(String sqlCommand, ExecutionTypes executionType)
   at Microsoft.SqlServer.Management.Common.ServerConnection.ExecuteNonQuery(StringCollection sqlCommands, ExecutionTypes executionType)
   at Microsoft.SqlServer.Management.Smo.ExecutionManager.ExecuteNonQuery(StringCollection queries)
   at Microsoft.SqlServer.Management.Smo.Agent.Job.StartImpl(String jobStepName)
   at Microsoft.SqlServer.Management.Smo.Agent.Job.Start()

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SQLServerAgent Error: Request to run job B01-BI Databases Backup.Full (from User sa) refused because the job is already running from a request by User sa. (.Net SqlClient Data Provider)



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Server Name: B01\BI
Error Number: 22022
Severity: 16
State: 1

Please suggest the solution.

Thanks