php - Pregmatch が PHP で正しく一致しない

Question

ここで何が起こっているのか理解に苦しむ。コード内のコメントで説明します。前もって感謝します。読みやすくするために、DB 部分への書き込みなど、いくつかのコード ビットが欠落しています。しかし、問題はこれらの行に限定されています。

if (filter_var($email, FILTER_VALIDATE_EMAIL) == TRUE and 
preg_match("/^[\w ]+$/", $address_one) == TRUE and 
preg_match("((?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%]).{8,20})", $password) == TRUE) {
//When given a valid email/address/password the code successfully gets to this point and inserts into a DB

} else {
    //When it fails validation with an invalid email/password/address it drops in here
    //but then it doesn't change error code variable...
    $errorcode = "IHAVENOTCHANGED";
    if (filter_var($email, FILTER_VALIDATE_EMAIL) == FALSE) {
            $errcode = " email,";
    }
    if (preg_match("/^[\w ]+$/", $address_one) == FALSE) {
            $errcode = " address line 1,";
    }
    if (preg_match("((?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%]).{8,20})", $password) == FALSE) {
            $errcode = " password,";
    }
    writetolog("LoginCreation", "Login failed due to invalid input: " . $errorcode . " - user: " . $email);
    echo "Invalid data for $errorcode please try again -- ADDRESS=$address_one -- EMAIL=$email -- PASS=$password";

}