nurakdoen mulgeon ttaemune banpumeul sincheonghaessseupnida.

누락된 comes from the verb 누락되다, which means to be omitted, to be left out, or to be missing from a list/order/package.

So:

• 누락되다 = to be omitted / to be missing
• 누락된 = omitted / missing

The -된 part turns the verb into a modifier that describes the noun after it, so 누락된 물건 means the missing item or the omitted item.

In this sentence, it usually means something was supposed to be included, but it was left out.

They mean different kinds of missing.

• 누락된 물건 = an item that was left out or not included
• 잃어버린 물건 = an item that was lost

So if a seller forgot to include something in a shipment, 누락된 물건 is the natural choice.

If you personally had the item and then misplaced it, 잃어버린 물건 would make more sense.

물건 literally means thing, item, or goods.

In this context, it usually means:

• an item in an order
• a product
• something that should have been in the package

So 누락된 물건 is best understood as the missing item.

때문에 means because of.

So:

• 누락된 물건 때문에 = because of the missing item

It marks the reason or cause for the action in the main clause.

The sentence structure is:

• 누락된 물건 때문에 = because of the missing item
• 반품을 신청했습니다 = I requested a return

Together: I requested a return because of the missing item.

때문에 is a very common and natural way to express a reason, especially in written language or customer-service situations like this one.

Compared with other forms:

• -아서/어서 often sounds more like a straightforward cause in everyday speech
• 때문에 feels a bit more explicit: because of X
• it often appears in complaints, explanations, and formal writing

So in a sentence about a return request, 때문에 fits very naturally.

Because 반품 is a noun here, and it is the object of 신청했습니다.

Breakdown:

• 반품 = return
• 을 = object marker
• 신청하다 = to apply for / request

So 반품을 신청하다 literally means to request a return.

This is a very common Korean pattern:

• noun + 을/를
  • 신청하다

For example:

• 환불을 신청하다 = to request a refund
• 변경을 신청하다 = to request a change

This is an important difference.

• 반품했습니다 = I returned it
• 반품을 신청했습니다 = I requested a return

The sentence uses 신청했습니다, so it does not necessarily mean the return has already been completed. It means the speaker submitted or made the request.

This is very common in shopping/customer-service contexts, where you first request approval for a return.

신청했습니다 is the past polite form of 신청하다, which means:

• to apply for
• to request
• to submit an application

So 반품을 신청했습니다 means:

• requested a return
• submitted a return request

Because it ends in -했습니다, it is formal and polite. This style is common in writing, customer-service messages, emails, or formal speech.

Korean often omits the subject when it is obvious from context.

So even though there is no 저는 or 제가, the sentence is naturally understood as something like:

• I requested a return because of the missing item

In Korean, leaving out the subject is very normal if the listener or reader can infer it.

If you added a subject, you could say:

• 저는 누락된 물건 때문에 반품을 신청했습니다.

But in many situations, the shorter version sounds more natural.

It breaks down like this:

• 누락된 = missing / omitted
• 물건 = item
• 때문에 = because of
• 반품을 = a return + object marker
• 신청했습니다 = requested

So the overall pattern is:

[reason] + 때문에 + [object] + 신청했습니다

More literally:

Because of the omitted item, I requested a return.

Natural English:

I requested a return because of the missing item.

Not necessarily. Korean nouns usually do not have to mark singular vs. plural unless it matters.

So 물건 can mean:

• item
• thing
• goods

Depending on context, it could refer to one missing item or missing merchandise more generally.

If the situation clearly involves one item, English will usually translate it as the missing item. If multiple items were missing, the context would tell you that, even if Korean still says 물건.

Yes, that is the literal idea. But in natural English, omitted item sounds less common in everyday shopping situations.

More natural translations are:

• because of the missing item
• because an item was missing
• because the item was left out

So the Korean is slightly more formal/literal than the most natural everyday English wording, which is very common in customer-service language.

Yes, it is polite and somewhat formal.

The main reason is the ending -했습니다, which is part of the formal polite style. This style is often used in:

• customer inquiries
• complaint messages
• reports
• business communication
• written explanations

So this sentence sounds very appropriate for explaining a return request to a seller or support team.