Re-sign a protected build
The protected build is already zipaligned and unsigned. Sign it with your own release key and it's ready to ship.
Why it's unsigned
Appsolid never holds your signing key, so the output ships unsigned for you to sign with your own release key. Zipalign is already applied, so there's no need to re-align.
Sign the APK
Sign with apksigner from the Android SDK.
apksigner sign --ks release.keystore app-protected.apkVerify the signature
Confirm the signature is valid.
apksigner verify --print-certs app-protected.apkFor AAB
For AAB, use the Play App Signing flow when you upload to Play.