I've created a simple automatic 10% discount on my store, this can be seen in cart, but weirdly the price fluctuates, firstly displaying the discounted cost, then then reverts to the cost without discount.
If I then move to the checkout, no discount is applied:
The configuration is really simple:
automatic 10% on any product, minimum spend £5. The discount is active and running until Sunday.
I am using the Boundless theme, and HULKApps Infinite Product Options to customise extras. I am leaning towards this being an issue with Infinite Product Options because a flash of price change, but I don't know for sure.
It seems that you want to offer a discount to your vistors to buy your product.
It is better to send offers to someone who really won't buy without that offer and discount and leave the other person who is more interested, to come and buy on her/his own! So, I think it is better to manage messages and act more customized and personalized.
BestPush is a smart web push notification tool that sends the shop visitors personalized messages, containing their most interesting products and sometimes the minimum discount possible, to convert them into buyers!
It uses AI and machine learning to analyze the visitors' interactions with your shop to find out who is price sensitive and who is not.
I suggest you test it because it is Free up to 500 notification subscribers (that is, for several months)and all its features are available in this free plan.
Check it out here:
I hope you find it helpful!