Yes to all does not work even though it's an option

I have a script that I am using to migrate legacy users. I got the script from here:

It is designed to import a spreadsheet that I provide and migrate the users in it. When I run it it runs fine and imports the spreadsheet as designed and is successful in moving the users. The issue I have is, during the process it asks if you want to move the user and the choices are Y – yes, A – yes to all, N – no, and L – no to all. If I choose yes it works and moves to the next user and asks again. If I choose A for yes to all it moves the user and instead of moving on and doing the same to all the users it acts like I said yes and asks me again at each and every user. Does anyone there who is familiar with powershell know why the yes to all does not work as it should??