You missed your friend birthday. Write the letter where you need to mentioned - why did you miss it - say that you are sorry - invite her to celebration between you two

Hi Kate, I hope you are doing well, it was great to hearing from you. How are you doing? How did you spend your party? The main reason why I am writing to you is to apologize about my absence on your latest birthday. I am really sorry that I missed your party last evening, […]