You can enable or disable happy hours discount globally from settings > order tab
You can find label HAPPY HOURS
Orders
Go to settings > general settings > orders

Default service : Checked the service which users can place order.
User can cancel order : To enables, user could cancel its own order
User cancel order time : User could cancel order in given number of minutes
Order for veritication : User could resend order for verification in given number of minute.
Check duplication : To enable, Client place new order, will check duplication of IMEI number
Happy hours : To enable, you can set discount on any product for an hours or days. read more how to set service for happy hours
Master Pin : To enable, PIN number needs for client to place new order
Place order type : To display service with group or without group on place order page
Information position : Choose to display service information on top or bottom of page
Subscription reminder : System auto send email of subscription end within days to client before defined number of days. more about how to set service for subscription
Predefine replies : Used to attach predefine replies with reply order
Display order : Choose to display order on page in ascending or in descending