Resetting subscription & customers list with Customer & Subscription Manager

[pshop]

Hello.
Please help me with this one..

When I click the customers,
there are 2 options.

Customers and Subscription Manager.

How do I reset the 2 lists?
Its just too much work to delete each one manually..

Please help...

[pshop]

I was able to reset the subscription list by using the top right remove button.
After pressing the remove button, the button turned into install button. So I pressed the install button and it gave a fresh subscription list.

I just don't know how I can reset the customers list.
Someone please help me....