Changing processor affinity works locally, but not on EC2 instance

Question

I am trying to start an application with a specific amount (in this case 4) of cpu's using this command:

start /affinity F Application.exe

This works well for me locally, however using a c5.9xlarge instance this command has no effect on the processor affinity. Instead I have to adjust the affinity manually in the Task Manager. Does anybody know what could be the issue ?