Hey, @BrimGlobal! Welcome the the Community, but I'm sorry to hear you're having trouble with payments being processed in your checkout. Which payment gateway are you using? What exactly happens when a payment is attempted? Is there an error message?
Which theme are you using? Aside from downloading a fresh version of it, it is possible to roll back the code of your current theme to the version it was before you made the customization. The Help Doc for Editing theme code has the steps to do it within the section Roll back to an older version of your theme.
Let me know if this helps!
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