甚樣用英語拒絕新客做月結?

Dear Mr xx

In response to your recent request for the change of payment term from c.o.d to monthly settlement, we regret to inform you that we are unable to accept you request for the time being based on our company's credit policy. However, we shall be delighted to allow your account to be settled on monhtly basis if your monthly purchase exceeds $xxxxxx in the future.

We apologize for the inconvenience caused.

Yours sincerely
XXXXXXX

2009-06-24 23:49:23 補充：
以上是電郵(書面)版本，如果用電話就不必太 formal，可以口語化一點，以下的講法，給您參考:

2009-06-24 23:50:23 補充：
Hello Mr XX
Knowing that you want monthly payment instead of c.o.d., we have reviewed your account carefully.
I am so sorry.
Our credit policy doesn’t allow us to accept t your request because your current purchase hasn’t reached the required level.

2009-06-24 23:51:08 補充：
It should be no problem If your monthly purchase over HK$XXX.
I should say sorry again for the inconvenience caused.
If there is anything I can help, please let me know.

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