Error (-1)

My iPhone 7 was having issues with rapid battery drain, no service, and random restarting of device couple of times in rapid succession, so I tried to update the device's software, but there was an error message that stopped my update. Then I tried to recover the phone but my iTunes said error (-1) and now it is stuck in recovery mode. I tried hard reset to kick it out of recovery mode, but the device remains in it. I researched what error (-1) meant, but apparently, even Apple technicians do not recognize it. So what do I do now?