楼主好, I am sorry for not replying your e-mail in time as I was on a business trip. I am now in difficult times so that I am unable to make the payment. Let's talk about this later.
I am sorry that I can not reply the e-mail in time because I was on business.I am in difficulty now,which makes me are not able to pay the fees.Please wait for some time
I'm sorry for not replying your email promptly because of the business travel. I'm hard up at the present and not able to pay the fee. Let's talk about it later.
Very sorry, i was unable to reply the email on time due to a business trip. I am going through a fiancial difficulty right now and will not be able to pay right away, so please wait patiently for a short period of time!