Dear Mark,
Thank you for your email.
Due to unforeseen events, I must cancel my registration. Since no other co-authors can travel to Lisbon on those dates, I also have to remove both of my papers from the conference program.
I am very sorry for any inconvenience this cancellation may cause the DRUID team. I did everything possible to enable my travel on those dates since I was keen to participate in this fantastic opportunity to present and discuss projects.
Please let me know if there is anything I need to do on my side to implement the cancellation.
Thank you,
Amir