Below are useful expressions of openings for replies to complaints :
- We are concerned to learn from your letter of …. that the goods sent under your order number …. did not reach you until ….
- We are sorry that you have experienced delays in the delivery of ….
- We note with regret that you are not satisfied with the goods supplied to your order of ….
- Thank you for your letter of …. which has given us the opportunity to rectify a most unfortunate mistake.
- We wish to apologize for the unfortunate mistake pointed out in your letter of ….