bimilbeonhoreul jalmos ipryeokhaneun barame baesong gisaga mos deureowassseupnida.

비밀번호 means password.

The particle -를 marks it as the object of the verb 입력하다 (to enter / input). So:

• 비밀번호를 입력하다 = to enter a password

In this sentence, the password is the thing that was entered, so -를 is the natural object marker.

Here, 잘못 means wrongly / incorrectly.

It is acting like an adverb that modifies 입력하다:

• 잘못 입력하다 = to enter incorrectly
• 비밀번호를 잘못 입력하다 = to enter the password incorrectly

A useful thing to remember is that 잘못 can mean different things depending on context:

• 잘못하다 can mean to make a mistake
• 잘못 before another verb often means incorrectly / by mistake

So in this sentence, it is not a noun like fault. It is simply describing how the password was entered.

This is a very common question.

The grammar -는 바람에 attaches to a verb stem and means because of doing X, usually with a negative or unfortunate result.

So:

• 입력하는 바람에 = because (someone) entered it
• with the nuance that this caused a bad result

Even though the action happened in the past, Korean commonly uses -는 바람에 with the present-style adnominal form -는 for action verbs.

So this is normal:

• 비밀번호를 잘못 입력하는 바람에...

It does not mean the action is happening right now. It is just how this grammar pattern is formed.

-는 바람에 means because of / due to, but it usually carries a feeling that the cause led to an unwanted, inconvenient, or unfortunate result.

So this sentence does not just mean:

• because the password was entered incorrectly

It also suggests:

• and unfortunately that caused a problem

That is why it fits well here: the delivery driver could not come in.

Compare:

• 비밀번호를 잘못 입력해서 배송 기사가 못 들어왔습니다.
  = The password was entered incorrectly, so the delivery driver couldn’t come in.
  This is fine and natural.

• 비밀번호를 잘못 입력하는 바람에 배송 기사가 못 들어왔습니다.
  = similar meaning, but with more of a regrettable consequence feeling.

So -는 바람에 is often used when something went wrong.

Yes, the subject is omitted.

Korean often leaves out the subject when it is understood from context or not important. In this sentence, we are told that the password was entered incorrectly, but the sentence does not explicitly say who did it.

Depending on context, it could mean:

• I entered the password incorrectly
• someone entered the password incorrectly
• we entered the password incorrectly

The sentence focuses more on the cause and result than on the person responsible.

Because 배송 기사 is the subject of 못 들어왔습니다.

• 배송 기사 = delivery driver / courier
• -가 = subject marker

So:

• 배송 기사가 못 들어왔습니다 = the delivery driver could not come in

The driver is the one who couldn’t enter, so -가 is correct.

A small vocabulary note:

• 배송 기사 literally means delivery 기사
• 기사 can mean driver, technician, or certain kinds of workers depending on context
• here it clearly means delivery driver / courier

This is an important distinction.

• 못 들어왔습니다 = couldn’t come in / was unable to come in
• 안 들어왔습니다 = didn’t come in

So:

• 못 emphasizes inability
• 안 emphasizes non-action / not doing

In this sentence, the reason is that the password was entered incorrectly, so the driver was unable to enter. That is why 못 is the better choice.

Compare:

• 배송 기사가 못 들어왔습니다.
  = The delivery driver couldn’t come in.

• 배송 기사가 안 들어왔습니다.
  = The delivery driver didn’t come in.
  This could sound like the driver chose not to come in, or simply did not come in for some reason.

The base verb is 들어오다, which literally means to come in / come inside.

It is made of:

• 들다 / 들어- = to enter
• 오다 = to come

So 들어오다 is often used from the speaker’s or destination’s point of view:

• to come in
• to come inside

In this sentence, the delivery driver was trying to enter the building or residence, so 못 들어왔습니다 means:

• couldn’t come in
• couldn’t get inside

If you used 들어가다, that would be more like to go in, which reflects a different point of view. Korean often chooses between 오다 and 가다 based on perspective.

It is usually written as two words: 배송 기사.

• 배송 = delivery
• 기사 = driver / technician / 기사

Together, 배송 기사 means delivery driver or courier.

In everyday English, you would usually translate it naturally as:

• delivery driver
• courier
• sometimes delivery person

-습니다 is the formal polite style.

So 들어왔습니다 is the polite formal past form of 들어오다.

That means the whole sentence sounds appropriate in:

• formal conversation
• customer service contexts
• speaking politely to someone you do not know well
• written notices or explanations

A less formal polite version would be:

• 비밀번호를 잘못 입력하는 바람에 배송 기사가 못 들어왔어요.

That means the same thing, but sounds more conversational.

Yes, 입력하다 is very commonly used for entering passwords, numbers, codes, and information into a device or system.

Examples:

• 비밀번호를 입력하다 = to enter a password
• 코드를 입력하다 = to enter a code
• 정보를 입력하다 = to input information

A more casual verb like 치다 can sometimes be used in speech for typing:

• 비밀번호를 치다 = to type a password

But 입력하다 sounds more standard and is especially natural in written or formal contexts.

Yes, it can.

Because -는 바람에 often highlights an unfortunate cause, the sentence can sound like the speaker is explaining what went wrong. Depending on tone and context, it may sound like:

• a neutral explanation
• a mild excuse
• an apology-like explanation

For example, if someone asks why the delivery failed, this sentence sounds like:

• The delivery driver couldn’t get in because the password was entered incorrectly.

It naturally suggests that the speaker is explaining the reason for the problem.