I also have a jbl flip 3 that keeps disconnecting during operation. I tried resetting the device (de-pressing vol+ and phone buttons while the unit is on until it switches off) however that was futile. I decided to try and fully drain the battery to see if will help and you what, it did. Once ur persistent at reconnecting the device, eventually it will begin to play for longer periods. Do this until the battery goes dead or the low battery red LED is blinking. Recharge your phone afterwards( LEDs would switch off when speaker is fully charged) and it should rectify the problem, at least it worked for me :)