seikyuuteisei wo onegaisuru.

It is read:

請求訂正をお願いする。
せいきゅうていせい を おねがいする。

• 請求 = せいきゅう
• 訂正 = ていせい
• お願いする = おねがいする

They are being used as a compound noun.

So 請求訂正 works like a compact business-style expression, similar to English noun stacks such as billing correction or invoice correction.

A more explicit version would be:

• 請求の訂正
• 請求書の訂正

Those sound a little clearer in many situations. The version without の is more compact and can sound businesslike, administrative, or note-like.

請求 can mean things like:

• a bill
• an invoice
• a charge
• a claim or demand

In a business or accounting context, it often refers to billing or an invoice-related charge. So here it most likely means a correction to something in the billing/invoice information.

The exact nuance depends on context.

を marks 請求訂正 as the thing being requested.

The pattern is:

N を お願いする = to request N

So here:

• 請求訂正 = the correction of the billing/invoice
• を = marks that as the object
• お願いする = to request

So the structure is basically request a billing correction.

お願いする is softer and more polite than 頼む.

• 頼む can sound casual, direct, or blunt
• お願いする is very common in polite requests, especially in business situations

So in office Japanese, customer-service Japanese, and email Japanese, お願いする is often the safer choice.

For example:

• 確認を頼む = more direct/casual
• 確認をお願いする = softer, more polite

It is in plain form, not full polite form.

That means お願いする here is the dictionary/plain form. It is natural in contexts like:

• notes
• headings
• explanations
• internal memos
• dictionary examples

If you were actually speaking politely to someone, you would more often say:

• 請求訂正をお願いします。
• 請求の訂正をお願いいたします。

So the expression itself is polite in tone, but the sentence ending shown here is still plain form.

The お is an honorific/polite prefix.

It makes the expression softer and more polite. In this case, お願いする is basically a fixed expression, and that お is normally kept.

So learners should think of お願いする as one standard expression meaning to request or to ask a favor.

Japanese often leaves out information that is understood from context.

So this sentence does not explicitly say:

• who is making the request
• who is receiving the request

Depending on context, it could mean:

• I request a billing correction
• We request a billing correction
• Request a billing correction as a note or instruction

If you want to show the person being asked, you can add に:

• 担当者に請求訂正をお願いする。
  Ask the person in charge for a billing correction.

It is very close in overall meaning, but the tone is a little different.

請求訂正をお願いする is more like:

• request a correction
• ask for the bill to be corrected

That is softer than directly saying:

• 訂正してください = please correct it

Japanese often prefers this kind of request-style wording because it sounds less direct and more polite.

It is understandable, especially in business-style shorthand, but in many real situations a native speaker might use something a little more explicit, such as:

• 請求の訂正をお願いする
• 請求書の訂正をお願いする
• 請求内容の訂正をお願いする

These versions make it clearer what exactly is being corrected.

So 請求訂正 is possible as a compact label-like expression, but fuller versions are often more natural in normal sentences.

Sometimes yes, but only in context.

The basic meaning of お願いする is to request.
When used as お願いします, it often functions like please in natural English translation.

For example:

• 請求訂正をお願いします。
  = Please correct the billing / I’d like to request a billing correction

So お願いする does not literally equal please, but it often creates that polite request feeling.