An apology note is a short letter or message in which someone expresses regret for something they did wrong and says sorry to the person they hurt or inconvenience. Full definition
The company also wrote a long apology note on the issue and is now replacing batteries on older iPhones at reduced prices. (indianexpress.com)
A preemptive apology note — in case the babies cried — accompanied the headphones, that were branded with the logo of George's tequila company, Casamigos. (havebabywilltravel.com)
Meanwhile, Clive Owen, so incendiary in «Closer,» awaits his own apology note from the Academy. (incontention.com)