Despite its older origins, email marketing is still a viable source of affiliate marketing income. Some affiliates have email lists they can use to promote the seller’s products. Others may leverage email newsletters that include hyperlinks to products, earning a commission after the consumer purchases the product. Another method is for the affiliate to cultivate email lists over time. They use their various campaigns to collect emails en masse, then send out emails regarding the products they are promoting.
You could try advertising more, for example, by putting up signs around the neighborhood, posting about it on social media, or having people you know spread the word. You could also try doing it in a different neighborhood that might have friendlier people, or do it in a time and place where there's likely to be a lot of people walking around the area (e.g., near a church before the end of a mass). https://buzzingofferbusinessinvesting.tumblr.com/