iPhone 7 - cannot obtain IP address from home WIFI

My building “upgraded” our WiFi router and ever since, my iPhone cannot connect to the internet through the network even though other devices are successful. It will connect to the router, but there’s no actual internet access and sometimes will say “can not obtain IP address”. I pulled up the network details on my computer and Xbox that both connect without a problem and I noticed that the subnet mask on my iPhone will show 255.255.0 rather than 255.255.255.0. What does this mean or what is it telling me?

I have tried setting up static IP addresses as well, but this subnet mask issue still happens each time.

Solution 1:

Reset network settings on the iPhone

1. Go to Settings.
2. Tap General.
3. Scroll down to and tap on Reset.
4. Choose the option to Reset network settings.
5. If prompted, enter your passcode to proceed.
6. Then tap the option to confirm that you want to reset network settings on your iPhone.

When the reset is finished, your iPhone should restart on its own and then loads up the original network configurations. Don’t forget to reconnect to your Wi-Fi network to get back online and use online services.