A complaint letter

1. Header

1.1. Sender's Adress

1.2. Sender's Name

1.3. Date

1.4. Recipient's Name or Job title

1.5. Recipient's Address

1.6. Salutation

2. Closing & Signature

2.1. Closing mark

2.2. Signature

3. Body

3.1. Purpose

3.2. Problem's description

3.3. Problem's effect

3.4. Expected/ Suggested solution