You're looking for a guide related to vbmeta and Samsung M31.
This is a security lock triggered by Vaultkeeper or Prenormal RMM state. vbmeta samsung m31
You flashed a custom recovery or a rooted boot image without successfully disabling VBMeta first, or the data partition is encrypted and needs a format. You're looking for a guide related to vbmeta and Samsung M31
On your M31, go to and tap Build Number 7 times to unlock Developer Options. vbmeta samsung m31