My name is Lilith, I'm on the Social Care team at Shopify.
This particular error shows up when information about the store is missing. This would mean that any information that is under your Settings > General isn't fully complete.
Please make sure that you have everything filled out in there including a valid address and phone number.
Once you've updated this, you'll be able to activate Shopify Payments when logged in as the Account Owner.
If you've done this and still get that error, I'd be happy to take a closer look for you. Just let me know here if you still have that situation and I'll send over an email where we can securely address the error.
Let me know how you do with the information above! I'm happy to answer any questions you think of as you work on your business.