By "amendment for the company name", do you mean they are going to adjust the name of the company on their documentation? If this is the case, then here's my rewrite.
We shall amend the LC to show the correct beneficiary name. Please, submit the amendment fee of 350.00 HKD. As well, please, send us the original document when you receive the amendment to the company name from Helen.
note: I don't think it is necessary to use "accordingly".