How do i fix my door knob? on my back door when ever it closes it wont unfold...

on my back door when ever it closes it wont unfold i think its stuck but the constituent when u turn the knob the part that go in the door doesnt shift in adjectives the way OR it wont be in motion at all plz HELP ME PLLLLLLLLLLLLLLLLZZZZZZZZZZ
Answers:    Sounds resembling the recessed part that sits surrounded by the door frame (not the door) is out of alignment with the spring-loaded 'tongue' within the door. Check to see if it is too high, or low, or desires to be re-set forward or backward. The is usually a cover attached by two screw which can be removed, revealing the opening within the frame.Take the cover off and see if the door closes, after align the cover and adjust the opening as essential. Hope this helps.
I have the reverse problem with mine, it would plain but not pop back out to hold on to the door shut. Try to loosen but not remove the door knob, then raise or lower it to make it rank, then turn the knob and release a few times, when it is stratum and the thingy(the part when u turn the knob the segment that goes surrounded by the door) goes surrounded by all the bearing, tighten it up. If that doesn't work check back for a different answer, well brought-up luck!