Dear Jack,
How are you doing?
I am sorry to write this email to you regarding my unavailablity of traveling to Shanghai with you next weekend because there has an ungency from my company which needs me to have a busniess trip to Northern part in China next weekend. However, I an eager to travel to the Shanghai with you. So, could you please change the travel date to Shanghai? For my suggestion, I prefer to trvel to Shanghai the weekend after next weekend. What you do think?
I hope you can understand. Looking forward to seeing you in Shanghai soon.
Best,
Jun Li
Dear Jack,
I'm terribly sorry that I can't make it to go to Shanghai with you next weekend because of an unexpected urgency, and I have no alternative but to cancel our travel.
If it is convenient for you to adjust our trip to another day, please let me know your available schedule, and I won't let this happend again.
Looking forward for your reply, and again I'm sorry for that!
yours'
Li Jun