Hey there, Your screen or your proximity sensor could be defective. If not the proximity sensor could of gone bad from a drop. They are both replaceable, you can use your voice memo to test your proximity sensor by recording something and playing it back. Just put your finger over the proximity sensor and see if it blanks out or if they screen stays black. I would recommend you take the device to an experienced shop. The iPhone 5S is very touching with the 64 bit operating system and your phone could be destroyed with one wrong move. I would also try connecting your device too itunes and updating your software. Apple has been having a lot of issues with their software. Hope this helps. - Archie

Hey there, Sprint polices are pretty simple, the device may be used for international use. As long as the account the device was on is in good standing or paid off. As well as it had to be in service for 3 months before sprint will give you the unlock code so it can be used for international use. Sprint # 1-800-211-4727 for customer service - Archie

Hey there, Great news the LS980 and the VS980 are compatible for the digitizer LCD. Here is a LG G2 LCD and Digitizer Replacement ( LG G2 LCD and Digitizer Replacement ) If you have any questions just shoot me an Email - Archie