It is not necessary to use a comma before beginning a "so that" clause that comes second in the sentence. This is an adverbial clause, and, as I and many others see it, a comma does not precede an adverbial clause that comes as the second clause in a sentence. I understand you may have observed native speakers do the opposite, but it's really not correct punctuation.
What do you want to provide? The sentence doesn't make sense without this information.Please [provide the person in charge] at ABC bank so that we can advise our bank to contact him / her directly to ensure both LCs are cancelled.
It's not clear whether you want to help reduce the bank charge or eliminate the bank charge. Nevertheless, I corrected your sentence in the way I thought was best.We noted 15 pcs of U78 have been shipped to the UK by courier. Please, send us the related document in order to make payment. We will change the payment from LC to TT to help you reduce the bank charge.
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