Hi @Sanjk
You have been given a few troubleshooting checks before. Since no solution was found, see here.
Like the previous one, this is another simple technique to combat iPhone keeps crashing issue. Clearing phone's memory helps to release some storage space which also makes the phone work faster without any lag. There are many different ways to clear cache and memory on iPhone easily yet effectively like the one in the screenshot below, Go to settings>Safari>Click on clear history and website data.
These methods are pretty useful since if your phone can be clogged up with unnecessary data, most of the Apps and the iOS itself will not work smoothly because of which iPhone keeps crashing.
You can even try to restore your iPhone as another method to rectify the iPhone 6 crashing. You simply have to connect your iPhone to a PC/Mac>Open iTunes>Select your iPhone>Restore backup in iTunes>Pick the relevant one after checking date and size> Click Restore. You may need to enter the password for your backup.
However, please keep in mind back-up all your data as this restoring using iTunes results in data loss. For your convenience, we have also explained how to restore iPhone without using iTunes which helps you from data loss. This is done by using dr.fone toolkit- iOS system recovery.
Note: Both the processes are lengthy so follow the steps carefully to get the desired results to fix iPhone crash error.
