not sure if this could save my 6.5 band in writing

[gainer04]

I am not sure if this could save my 6.5 band in writing ( another .5 from task 1 General can add up to make it to the band 7 goal . ) Please help to check.
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You received a letter from your bank stating that you will be charged $35 for a banking service you didn't use.You know that this information is incorrect.
- Write what the erroneous banking service is
- explain why this is in error
- Describe what you would like the bank to do about it .
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Dear Sir ,

I am writing you in response to a letter that I received from your bank yesterday . As I understand , it stated there that there was a $35 that was charged on my account after completing a wire transfer. I would like to express my dissatisfaction about this as I am not aware of such transaction and paying a certain amount for a service that I did not even made makes me more worried.
It has been almost a week now that I have not accessed my account. Also, it is very unlikely for me to execute a wire transfer as I have not did it before. You can probably request to retrieve the details of my transaction history and I am confident that you will not find any money transfer that has been executed since the first day I opened up my savings account with your bank. Moreover, all of my bill payments and money transactions are set up in a way that it will be automatically be deducted from my savings fund at the end of the month .
I would like to point out that this kind of banking system failure can create unpleasant business relationship between us and even to your numerous clients. I suggest that you start your own internal investigation to address this system failure and immediately implement a corrective action.
As soon as you find out where is the disconnect , I demand a full proof that this will not happen again. Please immediately pull back the $30 charges you imposed to my account as well.

Yours Faithfully,
Mr.Gainer

[charles205]

Hi,
Noted that you are inconsistent on the bank charges, earlier it is 35 where you say it is 30 in the later part of your letter. Also, Better to say assurance than full proof. I feel still you can reduce your number of words.

[saqibali]

Sentences need revision/rephrasing
Secondly, some words are not correctly used.When you "insert" a word, imagine like you are filling in blanks and try to find the best suitable word from your collection.