Why Is iPhone 5s Dropping Calls?

There are two main reasons the phone would be dropping calls. They are both quick fixes and will not damage the phone.

1: The SIM card needs to be reset.

This is a common issue and is easily fixed by using a paper clip or push pin, turning off your phone, taking out the SIM card, (which is done by pushing the tip of the pin into the hole on the card slot and pushing on it until it pops out) and letting it sit for about 30 seconds before putting it back in and rebooting the phone.

2:The towers the phone uses need to be reset.

Also a common issue with an easy solution. Go to Settings>Cellular>Cell Towers>Reset Towers (It says Towers or Cell Towers and has a distinct icon next to it) and reset the towers the phone tracks and uses. Don't worry, it does not delete any data, memory, purchases, or content off the phone. Users may experience their service bar reading "Extended" and "Searching" more often than usual as the phone is trying to reconnect to the towers around it.

If you have any other questions, please post them here.