Unable to create Dynamic Action

Dear Gurus,

I Am trying to create a Dynamic action so that when  IT0002 Field for Children ANZKD is changed or created with a number entered , then IT 0021 subtype 2 ( children ) should be made available to be created or changed .

I created the following dynamic action but it is not working

IType   STy.    Field        FC    S     Variable function part

0002               ANZKD     06     I       INS,0021,2,01

OR 

0002               ANZKD     04     I       INS,0021,2,01

Please Guide !

Thanks,

Dana