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Check the balance before editing the network profile
A failed mobile data test is not always an APN problem. The line may be out of credit, the data bundle may be finished, the plan may be barred, or the phone may be using the wrong SIM for data.
Run the balance check first. If the account and data allowance look active, then continue to APN, signal, roaming and device checks.
Methods
Dialog Sri Lanka balance check options
| Need | Use | What to confirm |
|---|---|---|
| Balance and account menu | *#456# | Available credit, account status or main menu response. |
| Data usage check | MyDialog app or SMS myuse to 678 | Remaining bundle data, active package or plan route. |
| App or self-care | MyDialog app or MyAccount portal | Plan name, renewal date, postpaid bill or usage detail. |
| Support fallback | Dial 456 or use MyDialog if a postpaid, Home Broadband or corporate line does not show usage by USSD. | Whether the SIM, plan or service state blocks data. |
Dialog FAQ lists 456, #107#, *#456#, SMS bill to 456 and MyDialog/MyAccount routes for account checks; use the app for detailed data usage when available.
Order
Safe checking order
- Dial or open the balance route from the same SIM that is failing.
- Write down whether the reply shows credit, a data bundle, expiry date or a blocked service.
- Disable WiFi and open a browser only after the balance or data bundle looks active.
- If the account is active but data still fails, move to APN, selected data SIM, signal and roaming checks.
Guide
What the balance result means
If the code shows no credit or no data
Do not edit APN fields yet. Top up, activate a data bundle or wait for the plan to refresh, then test again with WiFi disabled. Editing network fields while the line has no usable data can create a second problem and make the original issue harder to prove.
If the code works but mobile data still fails
Check that the same SIM is selected for mobile data, especially on dual-SIM phones. Then confirm signal strength, preferred network mode, roaming status and whether VPN, private DNS, parental controls or work profiles are blocking traffic. Only after those checks should you compare the APN profile.
If the USSD code does not return a result
Retry once with stable signal and no active call. If it still fails, use the app or support route listed above. Some postpaid, tourist, corporate or roaming lines expose account information through a different menu, and some international networks do not pass every USSD request reliably.
When to change APN settings
Change APN settings only when the balance and plan are valid but browser data still fails. Record the current profile first, change one field at a time, save, select the profile, toggle airplane mode and test again with WiFi disabled.
Questions
Dialog Sri Lanka balance questions
Should I use the balance code before changing APN settings?
Yes. A correct APN cannot restore browsing when the account has no credit, no active data bundle or a barred service state.
Why does the balance code fail while roaming?
Some visited networks do not pass every USSD request. Use the carrier app or support channel when the code fails overseas.
What should I do if the balance is active but apps still fail?
Test a browser with WiFi disabled first. If browsing works, the remaining issue may be app cache, VPN, private DNS, hotspot permission or a regional service block.
Editorial notes
Review notes
We focus on safe device paths, carrier-specific caution and practical troubleshooting.
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Related guides
Continue with the closest setup path.
