Vietnam tourism is gradually attracting foreign tourists. However, many tourists have been "ripped off" when buying things, hiring taxis, renting houses... by a part of Vietnamese people.
When you encounter a "rip-off" situation, please save evidence and contact the information compiled by Hanoi Green Tour below, the authorities of Vietnam are committed to handling people who make Vietnam's tourism look bad:

Noi Bai Airport – Hanoi
Airport Security hotline: (024) 3.584.2627.
Noi Bai International Airport Police Station: (024) 3884.3241
Committee for Action on Passenger Service Quality: phone: (038) 916.6566 | Email: CS.han@acv.vn

Da Nang Airport
Hotline: 0905920019

Tan Son Nhat Airport - Ho Chi Minh City
Hotline: 028 3848 5634

Phu Quoc
Hotline: 0918 655 355

Ninh Binh
Hotline: 19000117
 
In addition, visitors should save the following national phone numbers:
113 - police number when encountering any potentially dangerous problems
114 - Fire department
115 - medical emergency
Currently, when needing to request support in emergency situations, people and visitors do not need to remember the function of each emergency phone number, but only need to call 1 of the 3 numbers 113-114-115 to receive support from the authorities. The location of the resident/tourist will be automatically provided to the operator. Thereby, the authorities can quickly identify the area in need of emergency support to coordinate the rescue force.