Checking mobile data stops after a phone update
| Step |
Action |
What It Fixes |
| 1 | Check your network status | Confirms if issue is network-wide |
| 2 | Toggle aeroplane mode on/off | Re-registers SIM on your network |
| 3 | Restart your phone | Clears temporary network errors |
| 4 | Check your network APN settings | Fixes incorrect data configuration |
| 5 | Re-insert SIM card | Fixes poor SIM contact issues |
| 6 | Contact your network support | Resolves account or SIM faults |
PUK stands for Personal Unblocking Key — an 8-digit code that clears a SIM blocked after repeated wrong PINs. Three bad PIN attempts blocks it; ten bad PUK attempts is permanent.
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⚠ Do NOT guess the PUK — 10 wrong attempts permanently destroy the SIM
Unlike the PIN (3 attempts), you get 10 PUK attempts total across all time. Entering the wrong PUK 10 times permanently destroys the SIM card — it cannot be unblocked and a replacement must be ordered. Only enter the PUK once you have confirmed the correct code from your online account, SIM packaging, or network customer service.
Clearing network caches to restore data (Phone Network Locked Fix)
There are a few ways to find a PUK code without picking up the phone to support:
1. Online account: sign into the network account through the UK APN Hub — the PUK usually appears alongside SIM details.
2. Mobile app: the network's app lists the PUK under account or SIM settings, in SIM details.
3. SIM card holder: the credit-card-sized carrier the SIM came punched from usually has the PUK printed on it.
4. Phone support: as a last resort, call the network and request the PUK once identity is verified. Find the number via the UK APN Hub.
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SIM safety checklist
Take the PUK from the account portal or SIM packaging, not a guess, since mistakes are permanent
Step 1Do not guessStep 2Find PUKStep 3Unlock SIMStep 4Set new PINStep 5Test service
Testing data with another SIM or network (Phone Network Locked Fix)
At the SIM card locked — enter PUK code prompt, enter the 8-digit PUK, choose a new 4-digit PIN, confirm it twice, and the SIM reconnects right away.
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SIM safety checklist
The real PUK is in the account or on the SIM packaging — guessing can destroy the SIM permanently
Step 1Do not guessStep 2Find PUKStep 3Unlock SIMStep 4Set new PINStep 5Test service
Last resort: factory reset network settings (Phone Network Locked Fix)
If preferred, the SIM PIN can be switched off via Settings → Security → SIM Card Lock, or changed to something easier there, at the cost of some security.
What happens with an incorrect PUK? (Phone Network Locked Fix)
The PUK allows ten tries. After ten wrong attempts, the SIM is unrecoverable, and a free replacement carries the number and account across automatically.
📶
SIM safety checklist
Locate the correct PUK via the account or SIM packaging rather than guessing, which risks a permanent block
Step 1Do not guessStep 2Find PUKStep 3Unlock SIMStep 4Set new PINStep 5Test service
!
⚠ Do NOT guess the PUK — 10 wrong attempts permanently destroy the SIM
Unlike the PIN (3 attempts), you get 10 PUK attempts total across all time. Entering the wrong PUK 10 times permanently destroys the SIM card — it cannot be unblocked and a replacement must be ordered. Only enter the PUK once you have confirmed the correct code from your online account, SIM packaging, or network customer service.
Frequently Asked Questions About Phone Network Locked Fix
Why is your network mobile data not working?
your network mobile data may stop working due to an incorrect APN, a temporary network outage, an expired data plan, or a SIM issue. Follow the steps in this guide to identify and fix the cause.
How do I reset my your network APN settings?
On Android: go to Settings → Network → Mobile Networks → Access Point Names, then tap the menu and select 'Reset to default'. On iPhone: go to Settings → General → Transfer or Reset iPhone → Reset → Reset Network Settings.
Does your network have a network outage in my area?
Check your network website or their social media channels for real-time outage information. You can also check third-party sites like Downdetector for user-reported your network outages.
Why does your network show signal but no internet?
If your network shows signal but no internet, the APN settings may be incorrect or missing. Check the APN settings on your device and compare them to the correct your network values in our APN guide.
How long does a your network outage usually last?
Most your network outages are resolved within a few hours. For planned maintenance, your network usually notifies customers in advance. Check your network status page for current updates.