CTGDIS183E Error while mapping attribute 'attributename' in the Input Attribute Map of Component

CTGDIS183E Error while mapping attribute 'attributename' in the Input Attribute Map of Component 'Feed' (Feed.Input.attributename). // attributename=any-attribute
com.ibm.jscript.InterpretException: Script interpreter error, line=1, col=12: 'conn.OUCID' is null
    at com.ibm.jscript.ASTTree.ASTMember.interpret(ASTMember.java:153)
    at com.ibm.jscript.ASTTree.ASTCall.interpret(ASTCall.java:88)
    at com.ibm.jscript.ASTTree.ASTMember.interpret(ASTMember.java:106)
    at com.ibm.jscript.ASTTree.ASTCall.interpret(ASTCall.java:88)
    at com.ibm.jscript.ASTTree.ASTProgram.interpret(ASTProgram.java:119)
    at com.ibm.jscript.ASTTree.ASTProgram.interpretEx(ASTProgram.java:139)
    at com.ibm.jscript.JSExpression._interpretExpression(JSExpression.java:435)
    at com.ibm.jscript.JSExpression.interpretExpression(JSExpression.java:421)
    at com.ibm.jscript.JSExpression.evaluateValue(JSExpression.java:251)
    at com.ibm.jscript.JSExpression.evaluateValue(JSExpression.java:238)
    at com.ibm.jscript.JSExpression.evaluateValue(JSExpression.java:241)
    at com.ibm.jscript.JSInterpreter.interpret(JSInterpreter.java:57)
    at com.ibm.di.script.ScriptEngine.interpret(ScriptEngine.java:940)
    at com.ibm.di.script.ScriptEngine.interpret(ScriptEngine.java:925)
    at com.ibm.di.server.AttributeMapping$SingleAttributeMap.eval(AttributeMapping.java:727)
    at com.ibm.di.server.AttributeMapping.mapAttribute(AttributeMapping.java:279)
    at com.ibm.di.server.AttributeMapping.mapEntry(AttributeMapping.java:508)
    at com.ibm.di.server.AttributeMapping.mapEntry(AttributeMapping.java:359)
    at com.ibm.di.server.AssemblyLineComponent.getnext(AssemblyLineComponent.java:954)
    at com.ibm.di.server.AssemblyLine.msGetNextIteratorEntry(AssemblyLine.java:3689)
    at com.ibm.di.server.AssemblyLine.executeMainStep(AssemblyLine.java:3388)
    at com.ibm.di.server.AssemblyLine.executeMainLoop(AssemblyLine.java:3000)
    at com.ibm.di.server.AssemblyLine.executeMainLoop(AssemblyLine.java:2983)
    at com.ibm.di.server.AssemblyLine.executeAL(AssemblyLine.java:2952)
    at com.ibm.di.server.AssemblyLine.run(AssemblyLine.java:1319)

Very basic error, It comes during attribute name gap in input file and AL input map attributes.
easily just compare both and fix the error.