Unable to update software

iPhone 5s, iOS 12

iOS 12.5.7 is the latest iOS security update for iPhone 5s.

Go to Settings -> General -> Software Update -> Download and Install (if you haven't already done that).

iPhone 5s can’t be update to a higher iOS (13 and later). 

Most apps require iOS 13.4 or later.                                

Considering a newer type of iPhone?

Read this before you buy a newer type iPhone.