Letter of apology - re: delay in replying
Thank you for your letter of [date]. I apologise for the delay in dealing with your
original query, but I have been absent from the office for the last [enter time] -
and due to a most careless oversight, your request regarding [enter details].
I do apologise for this inefficiency and now enclose the [details] you require. If
you require any further information, please do not hesitate to contact me.