How can a customer and a seller cancel an order?

The customer has the option to cancel the order from his dashboard on the website after logging in.
The order can be canceled only before the shipping has commenced.
         
A seller doesn't have the option to cancel the orders. The seller must inform the admin to do so.
The admin can cancel the orders from Orders section in StoreHippo Admin Panel.
For more information, please refer:
https://help.storehippo.com/topic/orders