If you have successfully created the new discount in Shopify, but it didn’t auto-sync with Talkable, go to the coupon list edit/create page (All reports → Coupon lists) and check the “Enable Coupon List Shopify Auto Sync” checkbox. 

If this checkbox is disabled (you are unable to check/uncheck), it means this site already uses the Coupon Webhook and will be created automatically — no coupons can be directly uploaded to Shopify. Instead, coupons are delivered to Coupon Webhook URL and should be handled from there. If you’d like to turn on/off Shopify auto-sync, you’ll need to first disable the Coupon Webhook.