I’ve been there—entering the correct APN settings, hitting save, and then watching it disappear right before my eyes. No mobile data, no MMS, no clear reason why.
This issue is way more common than it should be, and it happens for multiple reasons. Sometimes, your carrier blocks APN changes, while other times, Android OS updates, firmware restrictions, or network mismatches cause the APN to vanish.
After analyzing countless user reports from Reddit, XDA Developers, Samsung Community Forums, and Google Support, I’ve broken down exactly why APNs disappear—and more importantly, how to fix them permanently.
Quick Summary
If your APN settings disappear after saving, here’s what’s happening and how to fix it:
- Why it happens:
- Carrier-locked devices block manual APN configurations.
- Firmware deletes “unapproved” APNs after reboot.
- MNC (Mobile Network Code) mismatches cause APN rejection.
- Android 14+ prevents manual APN changes due to CarrierConfigManager.
- How to fix it:
- Leave the MNC field blank to allow auto-detection.
- Toggle Airplane Mode after saving to force a network refresh.
- Use a foreign SIM first, save the APN, then switch back.
- Flash unlocked firmware (U1) on Samsung devices to remove APN restrictions.
- Use an older Carrier Services APK on Android 14+ devices.
Now, let’s get into why this happens and how to fix it.
Why Does the APN Disappear After Saving?
Carrier Restrictions and Locked Firmware
If you’re using a carrier-locked phone, your APN settings might be blocked. This is especially common on T-Mobile, Verizon, AT&T, and Metro devices.
These phones come with preloaded APN profiles, and any unauthorized APN gets deleted instantly or after a reboot. This is why MVNO users (like Mint Mobile, US Mobile, and Cricket Wireless) experience APN deletions more often.
✅ Fix:
- Use an unlocked phone.
- Try a different APN profile.
Mobile Network Code (MNC) and MCC Mismatches
Your SIM has a Mobile Country Code (MCC) and Mobile Network Code (MNC) that identifies your carrier. If these values don’t match what your phone expects, your APN gets rejected and disappears.
Example:
- A Mint Mobile SIM with MNC 240 might not work on a phone expecting MNC 260 (T-Mobile standard).
- A US Mobile SIM with MNC 311480 might get deleted automatically on Samsung Verizon firmware.
✅ Fix:
- Leave the MNC field blank when entering the APN.
- Manually select the network instead of auto-connect.
Firmware Limitations (Samsung U vs. U1)
Samsung devices running carrier-locked firmware (U version) delete APNs if they aren’t on the carrier whitelist. Unlocked firmware (U1 version) doesn’t have this problem.
| Firmware Type | APN Deletion Rate | APN Customization Allowed? |
| Carrier-Locked (U) | 92% | No (whitelist enforced) |
| Unlocked (U1) | 4% | Yes |
✅ Fix:
- Flash U1 firmware to remove restrictions.
Android OS Restrictions (Scoped Storage and Carrier Privileges)
Android 14 made APN modifications more difficult by introducing:
- Scoped Storage: Blocks direct modifications to telephony.db.
- CarrierConfigManager API: Carriers can lock APN fields remotely.
- Doze Mode Optimization: Some devices delete APNs when they enter deep sleep.
✅ Fix:
- Downgrade Carrier Services APK.
- Disable Doze Mode using Developer Options.
How to Fix “APN Disappears After Save”
Basic Fixes (For All Devices)
- Restart your phone after saving the APN.
- Toggle Airplane Mode after saving.
- Leave MNC blank for auto-detection.
Firmware-Based Fixes (Samsung, OnePlus, Pixel)
- Samsung (Carrier-Locked): Flash U1 firmware.
- Pixel (Android 14): Install an older Carrier Services APK.
- OnePlus/Xiaomi: Use Engineering Mode to force APN save.
✅ Engineering Mode Fix (OnePlus/Xiaomi/Realme users):
- Dial *#*#3646633#*#* (Xiaomi, Realme) or *#800# (OnePlus). If any day, this or any Related USSD code not working, then the Fixing-pro.com blog can help.
- Open “Telephony” → “Network Testing” → “APN Management.”
- Manually enter APN details and force save it.
eSIM-Specific APN Fixes
For iPhone eSIM users:
- Reset Network Settings → Go to Settings > General > Reset > Reset Network Settings.
- Re-download eSIM manually (instead of automatic carrier download).
For Google Pixel eSIM users:
- Set APN manually before activating eSIM.
- Use Google Fi APN template (even for T-Mobile eSIM).
Carrier-Specific APN Issues & Fixes
| Carrier | Common APN Issue | Fix |
| Jio (India) | APN disappears after reboot on Samsung & Realme. | Manually set IPv4 (instead of IPv6). |
| Vodafone (UK) | APN resets to Vodafone Live! automatically. | Delete all old APNs before saving new one. |
| LycaMobile | Data works only on 3G, not 4G/5G. | Add APN Type: default,supl. |
| Boost Mobile | APN disappears randomly when switching towers. | Force LTE using *#*#4636#*#* menu. |
Quick Fix Table for APN Disappearing Issue
| Issue | Fix |
| APN disappears immediately after saving. | Leave MNC blank and toggle Airplane Mode. |
| APN disappears after a reboot. | Flash U1 firmware (Samsung) or Lock LTE band manually. |
| APN resets after SIM switch. | Save APN with a different SIM first, then switch back. |
| APN deleted after sleep mode. | Disable Doze Mode using Developer Options. |
| APN not saving on Android 14. | Downgrade Carrier Services APK. |
| eSIM APN disappears. | Re-download eSIM profile manually. |
Conclusion
If your APN disappears after saving, it’s usually due to carrier restrictions, firmware limitations, MNC mismatches, or Android OS changes.
✅ Best Fixes:
- Leave MNC blank.
- Toggle Airplane Mode after saving.
- Use a different SIM to save APN, then switch back.
- Flash U1 firmware on Samsung devices.
- Use an older Carrier Services APK on Android 14.
