Connection issues in Vietnam
Some users may experience problems accessing the Vietnamese language app. To fix the problem, you need to change the DNS settings on your device.
Android
Step 1: Go to Settings -> Network & Internet
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Step 2: Choose the Private DNS section
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Step 3: Set DNS address:
Google DNS: dns.google
Cloudflare DNS: one.one.one.one
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iOS
Step 1: Go to Settings -> Wi-Fi
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Step 2: Tap on settings (i) of the connected network
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Step 3: Choose Configure DNS section
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Step 4: Set manual DNS address:
Google DNS: 8.8.8.8
Cloudflare DNS: 1.1.1.1
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You can also use the app:
https://apps.apple.com/us/app/1-1-1-1-faster-internet/id1423538627