1234, Main Street
Boston, MA 02123
01 April, 2005
<Recipient Address Goes Here>
I am a customer of [Company name] since the last [Duration], and I was happy with your services till the last month.
However, when got my bill for the current month, I was forced to think that your services are getting more & more expensive than ever.
I didn’t understand why you people increased your rates, while most of the other providers are still charging a normal fee.
I need some explanation behind this increase in your rates. Please contact me as soon as possible. I may switch the company if I don’t get any response from your side.
encl: <List of enclosed items goes here>