Dear Visa Officer:
My last visa didn't arrive in Hong Kong, so I had to apply for a new visa for the following reasons:
1. The purpose of my last application for a tourist visa was to attend an exhibition in Hong Kong. Unfortunately, the visa was issued too late, and I missed the exhibition time, which is why I didn't go.
I want to participate in the exhibition again this year, and I hope I can get the visa in time.
Thank you very much for your consideration.
You are sincere.
XXX (first name)
Please adopt it, thank you!