We have the following serious problem in 5 live websites.
We have installed the latest version of Awocoupon and VP OnePageCheckout.
When we insert a coupon, the discount is calculated and appears in the cart just before the confirmation of the order.
When the order is completed, the price before the discount appears to the user and is used for payments.
I have contacted Jumbo from VP OnePage Checkout and after some research he answered me this:
https://www.virtueplanet.com/forum/vp-one-page-checkout/24614-problem-with-awocoupon-and-vp-onepage-checkout
It appears to be a bug in latest version of AWO Coupon Pro. It is removing the coupon codes every time the cart page is reloaded. It has added few VP One Page Checkout plugin specific codes in the component which is generating this issue.
As far as VP One Page Checkout plugin is concerned, we have not made any changes in the codes for coupons or for AWO Coupon.
I would suggest that you please contact the developer of AWO Coupon so that they can fix the issue.
Could you check and resolve the issue please?