Dear Sir or Madam, 
I have been a satisfied customer for several years, but I am writing regarding the cell  
phone
 bill I received on 17 th March 2015, which includes a total of $900 for international call charges. In fact, these charges are completely unjustified, for the following reason. 
At no time have I used Use synonyms
this
 Linking Words
phone
 to make international calls, either to my home country or to any other country. I used the Use synonyms
phone
 purely for local calls and for calls to government departments in London, which are national calls. I have checked my call summary, and there is no record of any
International connections. As you see, there is no possible reason for me to be charged for international calls, and Use synonyms
this
 is easily confirmed by my Linking Words
phone
 records. 
IUse synonyms
Add the comma(s)
, therefore,
therefore
 request that you withdraw these charges and change my bill Linking Words
accordingly
. I Linking Words
also
 ask you to confirm to me in writing that Linking Words
this
 has been actioned, by sending a copy of the revised bill to me at Linking Words
this
 address. 
I look forward to receiving your confirmation that all is in order. 
Kind Regards,
Mandeep Singh.Linking Words