Или
$_SESSION['R'] = $_SESSION['REG_INFO'] . '|' .
$_SESSION['REG_INFO_O'] . '|' .
$_SESSION['REG_INFO_B'];
Не подскижешь что с запросом?)
mysqli_query($CONNECT, "INSERT INTO `profile` VALUES ('', '$Exp[6]', '$Exp[5]', '$Exp[7]', '$Exp[0]', '$Exp[1]', '$Exp[3]', '$Exp[4]', '$Exp[2]', '$Exp[8]', '$Exp[9]', 'ttt', '1', '0', '/'"
$_SESSION['RF']=$_SESSION['REG_INFO'].$_SESSION['REG_INFO_O'].$_SESSION['REG_INFO_B'];
$Exp = explode(',', $_SESSION['RF']);