I am writing with regard to the (product/service) I received on (date)
• I’m afraid that it…(did not meet my expectations) (does not work properly), as I will explain below in more detail…
• Please could you look into this matter and advise me how you will rectify (/deal with) this.
• I look forward to your response (as soon as possible).
• I would appreciate your prompt response.
Second communication (no response to first email)
I refer to my previous email dated X with reference to…X
• I am very disappointed that I have not received a response to…X
• I would like you to deal with this matter urgently.
• If I do not hear from you within (state time limit) I will have to consider taking further action.
Second communication (unsatisfactory/satisfactory response to email)
Thank you for your reply to my email of (date).
• However, I am not satisfied with your response/offer/explanation. Please could you suggest an alternative solution or advise what further action I can take.
• I am very happy with your response/offer/explanation and thank you for your understanding and help in this matter.