A phone or tablet problem starting right after an OS update, a new case/accessory or a restored backup should be checked against that change first. For Android mobile hotspot, first confirm cellular works on the phone, disable VPN for one test and connect one nearby client.
What this covers
- Android mobile hotspot with this exact failure state
- Diagnosis across carrier/tethering plan versus cellular data, VPN, band and client compatibility
What it does not cover
Try in this order
0 of 4 completedCapture the exact failure state
ReversibleNote the exact update version, accessory or backup date, and confirm the feature worked immediately before it. Expected behavior: share an eligible cellular data connection over a supported secured Wi-Fi band.
Isolate the component boundary
ReversibleConfirm cellular works on the phone, disable VPN for one test and connect one nearby client. Test with the new accessory removed, or check the update's known-issues note for the exact symptom. Boundary to separate: carrier/tethering plan versus cellular data, VPN, band and client compatibility.
Correct only the proven cause
ReversibleCorrect the carrier setting, band compatibility or client network profile. Reset the one setting the update changed, or replace the incompatible accessory.
Verify and stop safely
ReversibleConfirm normal operation with the change present for one full day of typical use. Do not use open security or overheat the phone under prolonged tethering.
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