Same type issue with both an iphone 7 and an iphone 8. After updating ios, cell service is constantly 'searching' and both phones only work now on wifi. Can't adjust cellular settings because there is nothing under 'cellular' when I look in the menu. SIM card ID no longer shows up in settings/general/about (although the carrier does). Also can't reset network settings. Phone freezes for a bit after trying and then resumes operation, but never shuts down (and it doesn't help). Daughter's iphone 7 started having the issue 3 days ago. Son's 8 started yesterday. Chatted and talked for hours and hours with Apple.. did everything they came up with and nothing worked. Double checked the SIM card registrations with the carrier and even put a brand new SIM in the 7. Still nothing. Did a full restore after backup on the 7 and now it won't activate. Error message ranges from 'activation server is temporarily unavailable' to 'an update is required to activate your phone' (it's running 14.1.. fully updated). Hooking it up to my Mac, says activation information can not be obtained from the device. Have tried DFU multiple times. No change. Have not done a full restore on the 8 because of what happened with the 7. But the 8 is showing all the same issues (searching, nothing under cellular, network reset won't work, no SIM info in about menu, etc). Would love it if someone has any other ideas.