Some Samsung owners who installed the stable One UI 9 update say their phones no longer stay online. Posts on Reddit and the Samsung Community forums describe Wi-Fi that keeps disconnecting, mobile data that will not work and, on a few models, SIM cards that the phone does not detect at all.
Samsung has not commented publicly on the reports, and no permanent fix has turned up. It is also unclear how many people are affected: the evidence is forum threads, not a statement from Samsung or a carrier.
Samsung has been pushing the stable One UI 9 build to Galaxy phones for the past few months. Besides the redesign, it brings some Galaxy AI features to older flagships, so the update reaches a wide range of models, from budget A-series phones to foldables. That breadth is one reason a bug in the update could show up on so many different handsets.
The most serious reports involve mobile data. Posters on Samsung’s own forum say apps stay blank until they find a Wi-Fi network, and that a network-settings reset, airplane mode and taking the SIM out and back in changed nothing. One moderator’s advice was Safe Mode or a factory reset; a user answered that the reset had not helped either.
Android Authority gathered the complaints and has asked Samsung for a response.
Wi-Fi trouble is more widespread. Connections come and go with a “connection failed” error, and a restart fixes it for only a few hours. Odd patterns appear in the threads: a phone that rejects one home router but joins others, a handset that works on 2.4GHz but not 5GHz while every other gadget in the house copes, and a Galaxy Z Fold 7 whose Wi-Fi calling on T-Mobile stopped after the update.
One tip making the rounds is to open Developer Options, go to Connectivity Labs and turn off Wi-Fi 7 Mode. It will not work for everyone, since some owners cannot find that switch at all.
SIM detection is the rarest fault. A Galaxy A56 owner on Reddit says neither SIM is recognised and the diagnostics screen reports an empty tray; similar stories involve the A36, A52s and S24 Plus.
The spread across so many models points to a software fault rather than failed hardware, though nobody has confirmed the cause. If your phone has not yet taken the update, it may be worth waiting for Samsung’s reply, and if you are affected, backing up before trying a reset.
