A completed eVisa will be process within 3 - 5 working days, however it may extend further delay subject to immigration final decision.
An eVisa is single entry purpose only and valid to stay maximum 30 days from the date of arrival within the validity period.
According to Government of Vietnam, minimum of 30 days at least prior to the expiry date of your eVisa.
To track or resume your application, visit this link Status Checkand follow the provided guidelines.
Option1: Most of the Answers can be found in this FAQ section
Option2: You can raise question via the Contact us page.