Facebook doesn't return the Page and pixel with the account list — they need assigning.
Under "Ad accounts"
- The Owner, Head and Tech set the account's Page and pixel and save.
- AdFleet checks the IDs against what the token sees. If Facebook didn't answer, you can save only with "I'm entering it by hand, unverified" ticked.
In the launch form
- Page, pixel and Instagram can be picked right in the account's row — from what the token sees; unpublished Pages aren't available.
- No Page — the launch won't go: "No Page for: … — pick one in the account's row".
- Picked something other than the saved one and Facebook didn't answer the check — /help/launch-checks.
Why the pixel
Without a pixel the account won't launch a preset optimizing for pixel conversions. Pixel registrations and deposits in Stats and auto-rules come from it too.