My issue is resolved. Evidently upgrading my home Xfinity router to one that supports Wi-Fi 6E as opposed to Wi-Fi 6 made a difference.
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As a recap, in March 2025 I upgraded my iPhone SE third generation to iOS 18.3.1. Before this upgrade, I had no problems with my phone and it’s ability to use wi-Fi.
At the time I had an xB7 Wi-Fi router from ISP Xfinity; it was a 802 11 AX router w wifi6.
When the phone upgraded to 18.3.1, on any occasion when it was connected to my home Wi-Fi, I would have Internet access for about 3 to 5 minutes, then the Internet will drop out. The signal was stay strong, I was still able to see other devices in my home on my network, just no Internet. After turning off the wi-Fi on my phone and turn it back on after a few minutes/an hour/later, the Internet would restore, but again just temporarily, for 4 to 5 minutes. Going through all of the recommended solutions, including forgetting the SS ID, resetting the net work on the iPhone, did not resolve the issue.
Past that, upgrading to 18.3.2, then upgraded to 18.4, up to the current 18.5, did not resolve the issue, although with 18.5 they seem like the connection lasted a little bit longer, but again it will eventually drop out. Strong signal, no Internet.
Normally I do not connect my iPhone to hotspot such as you would find a Starbucks and hotels; I only connected really at home, at work and when visiting a relative residence. In all of those circumstances, I suffered the same issue with the phone connecting fine, receiving a strong signal, but Internet would only last about four or 5 minutes.
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Finally, I happen to read that an upgrade was available for my Xfinity router, moving it up to the next model xB8, which was also 80211 AX, but used wifi 6e. In addition to what was more than likely upgraded hardware and software to deal with the newest protocols, they only other difference that I could immediately discern was at the XB8 router - other than Wifi6E as opposed to Wifi6- allows more clients per is 3 frequencies: 2.4, five and 6 GHz. The XP eight allows 100 clients per frequency, with the XB7 allow 75.
Once the new router was installed, my problems with my iPhone and his Internet connection went away. I guess it's due to the fact that the previous router I used was wifi 6 and then the current router has an upgraded Wifi 6E.
Of course I am shooting from the hip on this, because I really don’t know for sure, but it almost seems as if the iOS upgrade that caused me to have these issues was trying to use the new 6ghz band, and Wifi 6E just does it better.
I am not sure obviously. But the fact that for me, Internet via Wi-Fi would exist for a few minutes then it would drop always after 4 to 5 minutes, coupled with the new protocols of Wi-Fi 6E and 802 11 AX, coupled again with the fact that my other family members, who have newer iPhones, did not encourage any of my difficulties, leads me to believe that there may have been some issue with the switching property that the routers have now to work with devices so that the devices can choose between the 3 frequencies. It would explain why I sometimes have Internet and then it will go away, as opposed never having Internet at all.
