混乱させてしまい、大変申し訳ございませんでした。
表記を英語に訂正した請求書を、再度お送りいたします。
以前に送った請求書は破棄していただければ幸いです。
ご指摘いただいた文章ですが、it が何を指すか分かりにくかったのは、テキストエディタからメールに文章を移す際、私が順番を間違えてしまったのが原因です。こちらも大変申し訳ありませんでした。
荷物が届くまでお待ちください、の意味でした。
SAL便は到着までに3週間ほどかかるようですので、お支払いは到着後確認後でも構いません。
I will resend the invoice with descriptions corrected to English.
Please discard the invoice sent previously.
Regarding the text you pointed out, the reason what "it" meant was unclear was because when I moved text from text editor into email, I put them in wrong order. I'm very sorry about this, too.
I meant that please kindly wait till the parcel arrives.
It seems like SAL takes about 3 weeks till delivery, so you can make payment after you receive it.
I will send the invoice to you again after correcting it in English.
It would be helpful if you throw the old invoice away for me.
Regarding to the sentence you pointed out, why "it" was unclear is that it was my mistake when I transferred the sentence to the email from the text editor.
I'm very sorry about it too.
it meant that please wait until the package arrives.
It seems it might take 3 weeks to deliver with SAL, it is okay you pay for it after confirming the item's arrival.