Chosen Solution
Sometimes when my iPhone 7 Plus looses cellular service, which happens a lot in my area, the Wi-Fi will drop out forcing me to disable and enable Wi-Fi again to get it working again.
That is way too little information to work with. For example you should provide information like this: exact model of the phone, for example iPhone 7 Qualcomm or Intel, Current condition and repair history of the phone. Which area Which carrier What cellular service, specifically what band. What kind of Wi-Fi, the technology, band and other parameters. Those should help a little with diagnosing inter-band interference issue, if that is the actual issue.
