my subscriptions cannot sync

hi

I recently created replication and some of subscriptions are in error state and when i want to sync :

TITLE: View Synchronization Status
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The agent could not be started.

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft%20SQL%20Server&ProdVer=11.0.5058.0&EvtSrc=Microsoft.SqlServer.Management.UI.ReplUtilitiesErrorSR&EvtID=CantStartAgent&LinkId=20476

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ADDITIONAL INFORMATION:

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

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SQLServerAgent Error: Request to run job C******-*****ting(from User ***\r*****) refused because the job is already running from a request by Start Sequence 0.
Changed database context to '*****'. (Microsoft SQL Server, Error: 22022)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft%20SQL%20Server&ProdVer=11.00.3156&EvtSrc=MSSQLServer&EvtID=22022&LinkId=20476