One UI 9 Broke Galaxy Wi-Fi? Try These Fixes Before a Factory Reset

Some Samsung Galaxy owners are losing reliable Wi-Fi, mobile data or SIM detection after installing One UI 9. The reports span several phone families, so there is no single model-specific explanation—and Samsung has not announced a universal repair yet.

The timing matters. Samsung began its official One UI 9 rollout on September 16 with the Galaxy S26 series after the software debuted on the Galaxy Z Fold8, Z Fold8 Ultra and Z Flip8. The rollout then reached models including the Galaxy S24 series, Galaxy A55 and newer foldables during October. Samsung’s own community now contains reports of phones briefly connecting to Wi-Fi, dropping the link and returning a “Failed to Connect” message.

That pattern points toward a software problem, but it does not prove every post-update connection failure has the same cause. A router fault, saved password problem, carrier outage or third-party app can look similar. The useful response is to test the least disruptive fixes first and preserve evidence before erasing anything.

Start with the fixes that do not erase your phone

Restart the Galaxy phone, then forget and rejoin the affected network. Open Settings > Connections > Wi-Fi, press and hold the network name, choose Forget network, and reconnect with the password. Also restart the router and check whether another phone or laptop can use the same connection. If every device is offline, the Galaxy update is probably not the immediate cause.

Next, test the phone on a second Wi-Fi network or a mobile hotspot. A Galaxy phone that fails on multiple networks gives you much better evidence of a device-side problem. If only one router triggers the failure, update that router’s firmware before changing more phone settings.

Samsung’s official troubleshooting guide recommends Safe mode as another dividing line. Open the power menu, touch and hold Power off, then tap Safe mode. Wi-Fi working normally there suggests a recently installed app may be interfering. Restart the phone to exit Safe mode.

Reset the radios, not the entire device

If the problem survives those checks, go to Settings > General management > Reset. One UI separates Reset mobile network settings from Reset Wi-Fi and Bluetooth settings. These options do not delete apps, photos or documents, but the Wi-Fi and Bluetooth reset removes saved networks and paired accessories. Have the relevant passwords nearby before confirming it.

Reports from affected users indicate that a restart or a quick airplane-mode cycle can restore connectivity temporarily. That can keep a phone usable, but it is a workaround rather than evidence that the underlying fault is gone. The same caution applies to disabling Wi-Fi 7 inside Samsung’s hidden Connectivity Labs menu: it has helped some owners, failed for others and is not available on every model. Changing an undocumented developer setting should not be the first step.

For mobile-data trouble, confirm that the SIM is detected, airplane mode is off and the carrier has no outage. Then use the separate mobile-network reset. If the phone shows no SIM after the update, record the software version and the result of Samsung Members diagnostics before reseating a physical SIM or contacting the carrier.

Do not rush into a factory reset

A factory reset deletes local data and forces a full setup. Samsung therefore tells owners to back up photos, videos and documents before using it. More importantly, user reports show that a reset has not fixed every One UI 9 connectivity failure. That makes it a poor early experiment when lower-risk diagnostics have not been exhausted.

Before considering one, check Settings > Software update > Check for updates and install any newer maintenance release offered for your exact model and carrier. Then send an error report through Samsung Members soon after reproducing the failure, so its diagnostic log captures the event. Note whether the fault affects Wi-Fi, cellular data, SIM detection or all three; include the network type and the steps already tried.

If connectivity is essential for work, authentication or emergency contact, use a known-good backup device while the Galaxy phone is unreliable. Owners still within warranty should contact Samsung support before opening the phone or repeatedly wiping it. Until Samsung identifies a common cause, a careful diagnosis is more valuable than a dramatic reset that may erase data without restoring the radio.