One day my iPhone 6 plus on IOS 9.3.3 randomly restarted and since its running Pangu IOS 9.3.3 semi-untethered jailbreak i had to re-jailbreak using the Pangu app. So i re-jailbroke ( or so i thought) and the device restarted and to my surprise the device wasn't re-jailbreaking at all. So i tried to re-jailbreak again and nothing, still wasn't jailbreaking. I thought i had installed a bad tweak or something messed up and honestly i was scared . I know I'm not the only person this has happen too. and if this has happen to you CONGRATS you came to the right place because i have found a fix quite annoying but it fixes the problem lol just follow these steps below.
Turn off your iDevice and leave it off for 10-20 seconds
Turn on your iDevice BUT THIS TIME HOLD DOWN THE VOLUME UP BUTTON WHILE ITS TURNING BACK ON
Once the device is back on unlock your device and open the multitask center (Double click your home button) and clear all apps EXCEPT FOR THE PANGU/PPJAILBREAK APP from it Now open your PPJailbreak or Pangu app and re-jailbreak the device once your iDevice restarts your device should be jailbroken (IF NOT DO NOT WORRY JUST REPLACE STEP 3 WITH STEP 6)
( ONLY USE THIS STEP IF THE INSTRUCTIONS ABOVE DID NOT WORK) Do all the steps over but this time for step 3 your going to clear all apps from the multitask center including the PPJailbreak/Pangu app then after it restarts your jailbreak should be back
*************NOTICE*****************
This method could take a couple of tries usually takes me about 3 tries the first time took me like 10 tries lol but after you get the hang of it. It's important to be patient and just keep trying. this method will fix your iDevice from not wanting to re-jailbreak. This method will not fix if you have installed a bad tweak. thank you and hope this helped someone out there.