if ($row["Username"]  == $testname){
    echo "Account name is already in use.<br>";
}elseif($row["Email"]  == $testemail){
    echo "Email is already in use.<br>";
}else{
    $sql = "INSERT INTO users (Username, Password, ID, Email, Firstname, Lastname) VALUES ('$testname', '$testpass', $testid,   '$testemail', '$testfirstname' , '$testlastname')";
    $conn->query($sql);
    echo "Account has been created.<br>";
}