Input your Apple ID email. This is required to sign the app so the old iOS firmware will trust it.
Installing Netflix on iOS 5.1.1 (most commonly found on the original 1st-generation iPad) is challenging because the current App Store version requires much newer hardware and software. However, it is still possible through specific workarounds using Apple's "Last Compatible Version" feature or manual sideloading. netflix ipa ios 5.1.1
The specific you receive when attempting to log into Netflix? Input your Apple ID email