Are you using social media to advertise your offers, do you run print marketing campaigns with offers? Then have you tried to track these offers using landing pages specific to the offers?
If you are advertising a buy one get one free or a percentage off a product or service for a week or so, set up a landing page specific for that offer and then track the number of hits you receive on the page and even collect data on these pages.
Social media offers? Offers that are only available on social media, try using these for flash sales like with Instagram stories to offer an exclusive sale and discount code that is only valid for a day or two.