SSIS JOb Fails when Schduled from SQL server agent with Connection nd Error Error: Source:PKG Name Description: The connection XXXX is not found But executed when run stand alone

HI ,

When I execute a SSIS Package its executes perfectly but when scheduled thru SQL server agent it fails Error  Error:   Source:PKG Name      Description: The connection XXXX  is not found

I am not sure what could be the reason , the SQL server job log in is the same as the SSIS login