iPhone 7 stuck on Apple Logo and trying to reboot every few minutes after iOS install

Hi, I put iPhone 7 for iOS download and install without taking a backup and now phone is stuck on Apple logo on White background and trying to reboot every minutes. In the recovery mode in iTunes, went for Update option and the update is completed but still the problem persists. Can someone please help. Have lots of memories on this 128 GB phone that I'm reluctant to part with. Any other means to recover the data?