If you have sent a campaign to your customers, here's how you can redeem it in Posist. 

The process of billing your customer would remain the same. You will need to ask them for the mobile number.

Place their order as you would in the interface. Now, check what campaign was sent to the customer by clicking on "Loyalty"

If there are more than one campaign, you will see a list of rewards they are eligible to redeem. Ask the customer which reward they would like to redeem at the store. 

Select the reward that they want, and click on "send OTP"

The customer will receive an OTP, which you need to enter here. Enter the order value after redeeming the reward and bill them for the same.

Once the OTP is entered, the item/amount will be discounted, and you will see it in your interface.

It is important you add all your customers so that you can send more campaigns and increase profits and repeat visits.