Hi everyone, I’m currently facing a blocking issue during App Review, and I’d really appreciate some help from anyone who has experienced something similar. My app was rejected under Guideline 2.1 – App Completeness with the following message: “An error message appeared after trying to Sign in with Apple. Device: iPad Air (5th generation), iPadOS 26.1.” The problem is: I cannot reproduce this bug at all, even when testing under the same conditions. ✔ What I tested: Physical iPad Air M2 on iPadOS 26.1 Physical iPhone devices iOS/iPadOS simulators (latest Xcode) TestFlight build (clean install) Debug build installed via Xcode (device connected) In every case, Sign in with Apple works correctly: Authentication sheet displays properly Callback returns the credential User is created/logged in without error No crash, no rejected promise, no empty credential ✔ Environment Using ASAuthorizationAppleIDProvider + ASAuthorizationController Default Apple Sign In button No custom nonce/redirect modifications No backend processing at login (client-side only) Works 100% on iPhone and iPad on my side ✔ Additional context The app review team also noted a second point: They couldn’t locate a secondary subscription paywall, which is displayed only after dismissing the first paywall. I already clarified this with them, but I'm mentioning it in case it's related to the Sign in with Apple issue — maybe something in the sandbox environment is causing unexpected UI behavior. ❓ My question Has anyone already seen Sign in with Apple fail ONLY for the App Review team, while: It works in TestFlight It works via Xcode installs It works on the same OS version It works on the same hardware Could it be an issue related to: Sandbox Apple ID? iPadOS 26.1 on App Review internal builds? Reviewers blocking popup presentation context? Missing entitlement although everything is configured correctly? Presentation anchor issues specific to iPad? Any help or ideas would be greatly appreciated. I’ve been trying to reproduce this bug for hours without success, so any insight is welcome. Thanks!