Where should I come to extend visa if I want to do on my own?

You can come to the Immigration office below:

•  Immigration office in Hanoi: 44-46 Tran Phu, Ba Dinh District, Hanoi
• Da Nang: 78 Le Loi, Thach Thang, Hai Chau, Da Nang 550000
• Ho Chi Minh city: 196 Nguyen Thi Minh Khai, Ward 6, District 3, Ho Chi Minh city

Working hours: Monday-Friday (Morning: 7am – 11h30am; Afternoon: 1h30pm – 5pm) and Saturday (Morning time only)