If N3 and N4 absolutely refuse to work, the license check might be server-side (unpatchable). In that case, do not keep trying—use an alternative approach:
Generally refers to modifying the signature or basic license check. Patch Pattern N3/N4:
: If N1 and N2 are green, go ahead and "Launch" the app to see if the patch worked despite the N3/N4 failures.
Rooted devices have a much higher success rate because they can apply "Patches to Android," allowing you to keep your original app data and Google Play connection.