You may not be applying the right marketing strategies or your products do not come up to their needs. I don't know what you are selling but it's okay and sometimes you need to take a look at your products once again to guarantee its quality is its best.
Btw, do know you that customers love discounted goods so much? Besides Freeshipping for a few purchases, you can consider Upsell and Cross-sell.
Upselling and Cross-selling are such amazing strategies to retain customers and encourage them to buy more. Not only they can get the goods they need (target products) but you can also increase your sales gradually.
For more information of the app, see it here: https://apps.shopify.com/upsell-cross-sell-smart-tool?utm_source=ecommerceuniversity&utm_medium=foru...
Hope this do help, good luck!
Now you should look back into your website. I don't know what really your problems is. It can be ineffective running ads, not good in optimizing your website. But i want to share about optimization your store to attract customers and keep they stay longer is very important for each store => it will help u increase conversion rate. Running ads just helps you bring customers into your store, it not affects to sales and conversion rate significantly. It will depend your store website features: Is it friendly with customers to use? Is it increase customer's experience? Does it's visual and display catch customer's eyes? There are a lot ways to fix this problems like you can using apps/tools or hire shopify experts to help you have a better visual and fix problems.
For example, if u have low budget u can use apps to import reviews, which is the best way to prove reliability of your store. In Shopify appstore, there are a lots apps help you do these tasks such as Ali Reviews (app i'm current using, it will help you to gain trust and increase conversion rate, which is very important and last step of turning vistors into sales.U can use it to add Reviews without Restrictions, review Pop-up with Pre-Set Data which can show "pop-up" notification that someone review from your store and create a testimonial page. You can also customer or design display of reviews matching your store's concept and run CService campaignvia email.
Good luck to u.
If you happen to still be struggling after implementing the suggestions noted above, I run a successful ecommerce and fitness based ad agency that can help convert your traffic into real sales. I in no means want to force you to make this decision but if you feel that you would rather have your marketing strategy handled by professionals please feel free to email me at firstname.lastname@example.org, or take a look at our website scope16.com to see some of our testimonies of what we have done for gym brands in our area. Best of luck with everything!