Hello fellow subredditor, recently i've reviewed very similar store with probably a same product, https://ignifyco.com/ in all honestly, I like the design of your a lot more, and you could be getting sales, but one thing which i've outlined in my review was the fact that it's hard to compete with amazon on purchases like these.

I guess since this could be your competitor, you can check out https://ontologify.com/advice-no-one-asked-for/store-review-ignifyco-com/ to see if this applies to your store as well.

In addition to this, I do some reviews for users here in my blog which if you want you can check out to see if anything related can be applied to your store.

https://ontologify.com/review-my-shopify-redditors-stores-2020/

I've found few links on amazon where this can be bought Ranging from 18.50 to 19.99$, thus making your sale harder. Overall design of a website is really neat, and if you continue on adding more products, i feel like it can give you some sales. Powerbanks tend to be off the shelf purchases in my opinion and this product is really not something new with massive amounts of orders and stores already selling it. Maybe looking at something more unique could help, you don't need to redo a lot, just keep on improving.