This is Lana from Shopify. I see you are having some issues publishing your Facebook ad so I wanted to help you out here.
This particular error is something that we have seen after changes were made to Facebook Pixels in response to Apple's iOS 14 requirements, and Facebook has an information page on this for you here.
It requires domains to be verified and assigned to a pixel.
The first step is to check whether you have verified your domain in the Facebook Business Manager. To do this, you can follow these steps from Facebook. Here is what that should look like:
The next step is to make sure that you have assigned events to the store Pixel in the Events Manager. The steps for this are again outlined in Facebooks documentation to Configure events to use Aggregated Event Measurement. Do note that after adding events or making any changes here at all, you will need to wait at least 72 hours before you are able to publish any marketing activity. It should look something like this:
Please ensure that your primary domain in Shopify matches exactly with the domain verified within Facebook. Your primary domain on Shopify can be checked by going to Online store > Domains. For example, if the domain verified in Facebook is "abc.com" then you'll need to ensure that "abc.com" is your primary domain in Shopify. If the primary domain needs to be changed, in the right corner, click on Change primary domain and select the exact same domain that is verified on Facebook within the popup then Save.
If you have tried all of the above steps and you're still experincing issues, please contact us through our live support here so that we can investigate it further for you. The reason that I am redirecting you to that link is because we are currently unable to access your account info through the Shopify Community. When speaking with our support, you can also link this thread to save some time and show all of the troubleshooting that you have tried so far.
Lastly, I can see that you're trying to create an audience building ad, which is very exciting! Once you are able to sort out your current issue and publish your marketing activity, have you already thought about how you will receive any potential traffic that can come from this? As a suggestion, I think this would be a great opportunity for you to run a promotion/discount to encourgae that traffic to checkout and turn it into conversions!
Just in case, I have a guide from our help centre on How to Create Discounts. For more ideas on increasing conversions, you should also check out our Shopify Blog article on some of the Timeless Ways to Increase Conversions.
Let me know if you have any other questions at all.
Thank you for trying all of the steps. In this case, you will need to proceed by getting in touch with our live support through the link in my last post. As I mentioned, please do reference this community thread when you get in touch because that will show what you have tried already and will save some time in getting to your solution quicker. Thanks again! -Lana