Running a second brand on Meta: new Business Portfolio and shared assets

Quick answer

Each Agency AI install needs its own ad account and Page. If your Business Portfolio is new, Meta caps it at one ad account, so a second brand has nothing to connect. The clean fix: give the second brand its own Business Portfolio (which comes with its own ad account slot) and share any assets you want to reuse into it as a partner. Don't move assets between portfolios and don't cram both brands into one ad account.

Why not one ad account for both stores

Agency AI reads and optimizes at the ad account level. Two stores on one ad account means blended stats, blended Growth Plays, and campaign lists that mix both brands. Meta's own reporting has the same problem. Separate accounts keep each brand's history clean, which also matters when you want an account audited.

Step 1: create the new Business Portfolio

Go to business.facebook.com and open the portfolio switcher (top left). Click Create a business portfolio.
Enter the second brand's name, your name and a business email. Use the same Facebook profile that administers your first portfolio.
In the new portfolio, go to Business settings → Business info and complete the business details. Consider verifying the business. New, empty portfolios draw Meta reviews; see Meta restricted your account during setup.

Step 2: add an ad account to the new portfolio

In the new portfolio, Business settings → Accounts → Ad accounts → Add → Create a new ad account.
Name it after the brand. Set time zone and currency carefully; both are permanent once the account runs ads. Match the currency to the brand's Shopify store currency where Meta supports it.
Add a payment method under Payments.

If the second brand reuses a Page, Instagram account, dataset (pixel) or catalog that lives in your first portfolio, share them rather than moving them.

In the new portfolio, copy its ID from Business settings → Business info.
In the original portfolio, go to Business settings → Partners → Add → Give a partner access to your assets. Paste the new portfolio's ID.
Select the assets to share (Pages, Instagram accounts, datasets, catalogs) and set the access level. Full control is simplest.
Switch to the new portfolio and confirm the assets now appear under Accounts and Data sources.

A Page can only be owned by one portfolio, but it can be shared with many. Sharing leaves your first brand untouched.

Step 4: connect the second store to Agency AI

Install Agency AI on the second Shopify store.
Click Connect to Meta. In Meta's pop-up, select the new portfolio, then tick its ad account and the Page (and dataset, catalog, Instagram if you shared them).
In Settings → Meta account, confirm the selections and save.

If the pop-up shows no ad account for the new portfolio, Meta hasn't finished provisioning it or a restriction is pending. See Unable to locate an ad account and page.