Codesys v3.5 sp20+(32bit)

I hope to power up the specified axis through the following code,It worked.

PROGRAM PowerupTest
VAR
    MC_Power_0: MC_Power;
    Axises:ARRAY[0..5] OF SM3_Drive_ETC_DS402_CyclicSync.AXIS_REF_ETC_DS402_CS;
END_VAR

MC_Power_0(
    Axis:=Axis0, 
    Enable:=1 , 
    bRegulatorOn:=1 , 
    bDriveStart:=1 , 
    Status=> ,
    bRegulatorRealState=> , 
    bDriveStartRealState=> , 
    Busy=> , 
    Error=> , 
    ErrorID=> 
);

Now, to change it a little bit, I save Axis0 into an array first, and then pass the elements of the array into the MC_Power function block.
It doesn’t work properly anymore.

Axises[0]:=Axis0;

MC_Power_0(
    Axis:=Axises[0],   //Changed here
    Enable:=1 , 
    bRegulatorOn:=1 , 
    bDriveStart:=1 , 
    Status=> ,
    bRegulatorRealState=> , 
    bDriveStartRealState=> , 
    Busy=> , 
    Error=> , 
    ErrorID=> 
);

Could you tell me the possible reason?
I hope I can access all axes as an array.

Thank you.