Thank you for sharing your question with our network.
All Facebook Pixel errors or issues are now fully supported by the Meta team and there are a variety of articles on their Business Help page regarding pixels that I encourage you to review for additional feedback.
Based on the error message alone, I am curious to learn which 3 letter ISO currency code you are currently using in your store. For some reason or another, Facebook Pixel is unable to recognize it. I also realize why you may have assumed this is a theme issue, so I double checked to find similar reports with the Sense Theme though I did not come across anything.
Please double check the custom code you have added for tracking, in particular the AddtoCart events. I also encourage you to connect with the Meta Support team directly to confirm what the code should look like.
In addition, I invite other business owners and developers to share their feedback or recommendations with you here.
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