How To Write A Complaint Letter About An Employee Sample . Here is an example of a complaint letter: Sample complaint letter against employee's misconduct, misbehavior, rudeness, or unprofessional behavior to boss, manager, or owner. Complaint Letter Format Samples, How to Write a Complaint Letter? A from www.aplustopper.com My name is (name) and i would like to inform you of the unprofessional behavior i experienced at your place of business on (date) at (time). Continue to say that you have written a letter, which has the details in the letter. Stepwise process for writing complaint letter to human resources.