Everyone else in the house is online. Your phone sees the network, asks for the password, and then sits on Authenticating or Obtaining IP address before giving up. Because only one device is affected, you can skip everything to do with the router being broken and focus on the phone, which narrows the problem considerably.
The short answer
Forget the network on the phone and rejoin it, which clears a corrupted stored profile and fixes most cases. If that fails, reset the phone’s network settings entirely. Also check that MAC address randomisation is not fighting a router filter, because that is the modern cause people never think to check.
Read the error, it means something
- Authentication problem or incorrect password. The password is wrong, or the stored profile is corrupted, or the router is rejecting the device.
- Obtaining IP address, then failing. The password worked. The router is not handing out an address, often because its pool is exhausted.
- Connected, no internet. A different problem entirely, usually DNS.
- The network is not listed at all. Either it is hidden, or it is 5 GHz only and the phone is looking at 2.4, or the phone is out of range.
- Connects then immediately drops. Interference, a weak signal, or an address conflict.
Forget the network and rejoin
Go to Wi-Fi settings, select the network, and choose Forget. Restart the phone. Then join again and type the password carefully, watching for autocorrect capitalising the first character. This clears a stale profile and is the most effective single step.
Toggle airplane mode
On for ten seconds, off again. It resets every radio on the phone at once and occasionally clears a stuck state that nothing else touches.
Check MAC address randomisation
Modern phones present a different hardware address to each network for privacy, and sometimes a new random one after an update. If your router uses MAC filtering or a device allow-list, the phone appears as an unknown device and is refused. In the network’s settings on the phone, switch to using the device MAC rather than a randomised one, then reconnect.
Check whether the router has run out of addresses
If the phone reaches Obtaining IP address and stops, the router may have exhausted its address pool. Restart the router, which releases every lease at once. If this recurs, widen the address range in the router settings.
Confirm the phone is not blocked
Look in the router admin for MAC filtering, parental controls, a device block list or a guest network restriction. It is easy for a device to end up blocked by a parental control schedule set up months ago.
Try the other band
If the router broadcasts 2.4 GHz and 5 GHz separately, try the other one. A phone that cannot join 5 GHz may be seeing a channel restricted in your region, which is a real and confusing cause.
Reset network settings on the phone
This clears every Wi-Fi network, Bluetooth pairing and mobile setting, and rebuilds them from scratch. You will need to re-enter passwords afterwards, so it is not free, but it resolves corruption that forgetting one network does not reach.
Update the phone software
Wi-Fi driver bugs are real and are fixed in updates. If the problem started after an update, check whether a newer one is available.
Test the phone on a different network, such as a mobile hotspot from another phone. If it connects fine there, the phone’s Wi-Fi hardware is healthy and the problem is specific to the interaction with your router. If it fails everywhere, the phone’s Wi-Fi itself is suspect.
The MAC randomisation trap
This deserves its own explanation because it is genuinely new and catches experienced people out. Phones now generate a random hardware address for each network they join, so that networks cannot track you across locations. It is a good privacy feature.
The trouble is that anything on your router keyed to a device’s hardware address stops working: MAC filtering, fixed IP reservations, parental control schedules, and device naming. Worse, the phone can generate a new random address after a system update or after forgetting and rejoining the network, so something that worked for a year suddenly does not.
If your router uses any of those features, switch the phone to use its real address for your home network specifically. The privacy benefit only matters on networks you do not control.
Before turning MAC filtering on as a security measure, know that it is easily bypassed and mostly serves to cause exactly these problems. Strong WPA2 or WPA3 encryption with a long password is what actually protects a home network.
If nothing works
A phone that will not connect to any network, after a network settings reset and a software update, may have a hardware fault. Wi-Fi and Bluetooth usually share a chip, so a useful check is whether Bluetooth also misbehaves. Both failing together points at that chip. A factory reset is the last software step, and if the problem survives it, the fault is hardware.
Why does my phone say incorrect password when the password is right?
Usually a corrupted stored profile rather than a genuine password problem. Forget the network, restart the phone and rejoin. Watch for autocorrect altering the first character as you type.
What is MAC address randomisation and should I turn it off?
It gives your phone a different hardware identity on each network, for privacy. Turn it off for your home network if your router uses filtering or fixed addresses. Leave it on for public networks, where it does real good.
Will resetting network settings delete my data?
No. It clears saved Wi-Fi networks, Bluetooth pairings and mobile network settings. Photos, apps and messages are untouched.
Why does it get stuck on obtaining IP address?
The password was accepted but the router is not issuing an address, usually because its pool is full. Restarting the router releases all leases and normally clears it.
Can a phone case affect Wi-Fi?
Rarely, though a case with a metal plate for a magnetic mount can weaken the signal. It is worth testing if your phone connects only when very close to the router.
The bottom line
Forget the network and rejoin first, because a corrupted profile explains most single-device failures. Check MAC randomisation if your router uses any kind of device filtering, since that is the modern cause nobody expects. Reset network settings only when the simpler steps fail, and test on a hotspot to confirm whether the phone’s Wi-Fi works at all.
