i updated my htc one to 4.3 but everything got deleted and im still on 4.2.2

[Humam Tarakji]

hello, i have an htc one that i recently got, today it asked me if i wanted to upgrade my mobile to 4.3, i am on 4.2.2! i accepted the upgrade, after finishing the install.. the phone restarted itself, and when it started. i found that everything on my phone was erased, as if i did a factory reset, and it was STILL on 4.2.2! Please help!