[Q] Reset to Factory Erased Everything, How to Recover Files on Internal Storage topic

Guys, I do apologize if I created this thread on an inappropriate way. I'm desperate. I Updated my HTC One to Android 5.0.2 through OTA. As it's recommended, I did a Factory Data Reset. NOW EVERYTHING IS LOST, MY PHOTOS,MY CONTACTS AND SMS BACKUPS, EVERYTHING. I did Factory Data Reset Before, But It Never Erased those files. I Don't know whether its because of Android 5 or not. BUT PLEASE, IF ANYONE CAN HELP ME TO RESTORE THOSE DELETED FILES, I'd be MOST GRATEFUL. I DO APPRECIATE YOUR HELP. MY PHONE IS NOT ROOTED and it's Completely STOCK. I Tried Several Recovery Apps, However as HTC one only has Internal Storage, the File System is not known, therefore, None of them Detected it.
ONCE AGAIN, THANKS IN ADVANCE TO THOSE WHO CAN HELP ME WITH THIS, IT'S TRUELY VERY VERY IMPORTANT FOR ME TO RETRIEVE THOSE LOST DATA. THANKS GUYS ...