Dear [Name of the Customer]   We kindly ask you accept or sincere apologies for the inconvenience cause in respect to [the issue/ i.e. delivery of product/quality/wrong item dispatched etc.].   We invest high efforts in ensuring our customer’s satisfaction. In this case unfortunately, we did not meet your expectations. After careful review of the situation, we narrowed the cause to [explain the weak link: key staff changes, recent internal system update, office relocation, etc.].   As a testament to our strive for perfection, we have taken steps to ensure that this will never happen again by [clarify by some of the following: creating companywide training sessions, installing new back-up systems, creating an internal auditing team, etc.].   Due to this serious oversight, we are going to provide