Elias here with Shopify Support. Thank you for reaching out.
There's two areas in the admin to look into for taxes, so it's difficult to determine which one needs to be adjusted for your store without looking into your account. However, I'll include screenshots to best assist you in checking your product attributes and tax settings. The first thing is to ensure that your products are set up with 'Charge taxes on this product', this can be found in the Pricing section of each product. Here's a screenshot of what it looks like:
If your products are set up to charge taxes, then the next area to check is under your Tax settings (Settings > Taxes). Under the Tax calculations, there's a function to 'Show all prices with tax included '. You'll want to make sure this function is unchecked or the tax is accounted for in the price of the products. Typically, this function is common for stores that need to include the tax with their listing price (eg. European VAT). Here's a screenshot of what this function looks like:
I hope this helps resolve the issue. If you run into any roadblocks or if you have any other questions, don't hesitate to let me know!