This may be a Stripe issue but we're not sure as we need to know more on how coupon values are sent to Stripe from the plugin. Coupons that are set to not expire are expiring after 1 month for Stripe users - after 1 month they are charged full price. Please help us understand how the plugin communicates to Stripe so we can see where the issue is. My developer will add more information in subsequent posts as he continues to investigate. Thank you!