Missing files after 6.0 Upgrade

[AC Question]

After upgrading my Infinix X510 to Android 6.0 all of my files disappeared. This was on my internal storage. All the folders and files on the internal sd card were gone except for one recent download. However they still take up space on my phone. I have tried searching for them with hidden files turned on and found nothing. I also tried a recovery program but it would not recognize my phone when I plugged it in. The missing files included music, documents, pictures, videos and the folders they were in. My apps are still there but some do not work because their extra data and obb cannot be found. Please, what can I do to get the files back or delete them to retrieve my space? I do not want to reset to factory settings because I would have to update again.