Sorry for late back, i did a hard reset but this didn't work, but i would like to add something about this black spot, if this is a physical damage(Dead pixels) it should shows black spot in any taken photos, but some times when i shoot to light sources(lights, Sun) etc... the light goes through this black spot , so sometimes its completely disappear and sometimes it shows less black region, and when i zoom the black spot zooms too !, This thing confusing me. !