You are trying to make a call and your iPhone went from having signal bars to simply saying that it is ‘searching…’. If you are certain that you should be getting service where you are, here are a few things you can try to make certain that your SIM card is still working.
See also: iPhone 7 Microphone Problems
One of the best ways to clear errors and simple problems for your phone is to restart it. Sometimes programs running in the background can cause errors that prevent the phone from performing the most basic of functions. By turning the phone off, the phone is able to turn off these programs and clear any outstanding errors caused by them. Theoretically, these errors or problems will be resolved when the phone is restarted.
Sometimes, your iPhone may have accidentally changed some of the networks settings in order to maintain a connection to various cell towers as you travel. It is possible that a setting may have caused the new issue of your antenna not being able to find ANY cell towers. Try resetting your phone’s network settings to default
There is a chance that some debris or something has lodged itself in the small SIM card port in your phone. Grab a paper clip and gently eject the SIM card from your phone.
There should be a little hole on the side of your iPhone that is for the SIM card tray. Using the tool shown in the picture above or the end of a paper clip, gently press the tool or paper clip into the hole until the tray holding the SIM card is protruding out. Take the tray completely out with the SIM card. If you have compressed air, use it to gently blow out the empty port. Then place the SIM card tray back into the phone. Once in the phone watch and see if the network bars return signifying that the phone now sees the network again.
There is a chance that a recent update to the OS could be available that is causing the phone to have an error or bug resulting in the ‘searching…’ problem. Go to Settings -> General -> Update Software to see if an OS update is available to download.
The last resort before taking your phone to have the antenna possibly repaired is to restore your phone to the factory settings. It is critical that you backup the data on your phone before performing this as all apps, pictures, and other personal info will be erased from the phone.
To do this, hook your phone up to your PC and connect to it using iTunes. Once iTunes recognizes your phone, click on it. Then you should see a button that says ‘Restore iPhone’ next to ‘Check For Update’. Click that and allow the process to run. Once complete, you will need to redownload your desired apps and other info (pics and/or music) from your iCloud.
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