Trados autosave

 I was working on a large project that has 24.000 entries I have been working on it on and off and i was at the 12.000 mark. It did autosave on my work and some point 3 weeks ago i stopped to work on something else. When i returned to it i saw that it had not saved the last batch and the translated part stopped at the 7.000 mark.  What happened to that work.  Did it not save it?  How can i find it. (we had a power failure while it was open, is that the problem?  did it disappear? Please help