Hi Anil,
As you are working on Reactive, you won't be able to use a CheckEmployeeRole action built-in the platform as an action, and you also can do it on client side, rather than doing it on server side.
For that, I would suggest you to have a variable of type Boolean to hold if user has the HREmployee role, for example IsEmployee. Then on the OnInitialize event of your screen you add the following JavaScript to get if the user has the Employee role and assign it to the variable, something like this:
After that, you just have to enclose your button on the if and set the variable as your condition:

In this simple way, you can do it on client side instead of server side and take full advantage of Reactive.
Kind regards,
João