   for (uint8_t i=0; i<(sizeof validUserIDs / sizeof validUserIDs[0]); i++) {
     if(matrixValue == validUserIDs[i][0]){
       userShift = validUserIDs[i][1];
+      authenticatedUser = i;
       return true;
     }
   }
+  authenticatedUser = 0;
   return false;
 }
 

      Serial.println("STATE_ACK");
      digitalWrite(LED_UID, LOW);
      digitalWrite(LED_MSG, LOW);
      break;
    default:
      break;

      trellisButtonPress();
        if (isSubmitButtonPressed){
          getMatrixInput();
          Serial.println(encodeMessage(), HEX);
        // sendMessage();{ TODO
          updateReadArduinoStatus(STATE_ACK);
        }
      break;
    case STATE_ACK: // Waiting for acknowledge
