Work from the cheap fixes to the expensive ones. The expensive one is deleting the profile. The cheap ones are which line is allowed to use mobile data, whether data roaming is off, and whether you are physically in Vietnam on Viettel. The guides below are the ones we send people when a screenshot would take longer to interpret than a checklist.

The product facts do not change inside a troubleshooting guide. You still have 5GB of high-speed data per day, hotspot inside that allowance, no voice, no SMS, and no slow unlimited fallback. The day resets at 23:59 Vietnam time. If the 5GB is already gone, no APN tweak will bring it back before midnight. That looks exactly like a broken install, which is why the remaining-data page exists.

Install was supposed to happen on Wi-Fi before the flight. If you are reading this in an airport hall, you can still add the eSIM from the QR email over airport Wi-Fi, then apply the same line settings. If the QR will not scan, use the SM-DP+ details in the email. If the email never arrived, check spam and then write to support with the Whop order address. We would rather resend a QR than watch you buy a second plan at a counter.

A useful support message includes four things: the phone’s marketing name and, if you can find it, the model number in the about screen; whether *#06# shows an EID; whether the QR ever reached “installed”; and a screenshot of the screen where mobile data and roaming are set. “It doesn’t work” with no screenshot usually costs a day of back-and-forth. The same-day reply window is Vietnam time. If you are still in the arrivals hall, airport Wi-Fi is enough to send that email. You do not need the eSIM itself to be online in order to ask for help.

The guides are written for the product as it is sold today. 5GB high-speed, then a stop, then 23:59 Vietnam time. Hotspot shares that bucket. No voice, no SMS, no eKYC, no top-up on the same QR. If a forum post describes a different Viettel package with unlimited slower data or a phone number, it is describing a different package. Applying those settings here, especially data roaming on, is a common way to make a healthy profile look dead. Start with the no-data page if you are in the country already. Start with Get Started if you are still at home.