I'm a complete noob when it comes to horary so don't take my word for it.Since this is a question about an electronic device I would look at the third house, the third house ruler and Mercury.
The third house cusp is in Sagittarius and Jupiter is in the first house. Jupiter is square Mercury. Saturn retrograde is in the third house.
Maybe your phone is not working due to overuse (Jupiter = expansion, in first house = you), Mercury is in tenth house = high exposure, it's in Leo = heat, Sun.
Saturn (aging) retrograde is in the third house, your phone is probably also just too old (iPhone 5s).
The Jupiter-Mercury square could also mean that your battery is overused/overheating.