hey I send out a fleet of 40 LC and they are missing now and there is no battle reports so they were destroyed and they dont show up on the fleet screen section can somebody help me?

Split. Have you checked your Empire View?

yea it completely disappeared for about a hour and now its back

Rishard- There are still some unresolved glitches that crop up from time to time. It is possible that the planet you sent the fleet from may be experiencing one of these hard to pin down glitches. If this happens again, I suggest you do the following:
1) Check fleet screen to make sure that the "missing" fleet is not listed there. Sometimes (rarely) fleets don't show up in overview, but at least for me, they always appear in the fleet screen.
2) Make a note of the planet (or moon) you sent the fleet from, the fleet's destination, and the action the fleet was taking.
3) Try to identify the exact situation that results in your "missing fleet".
4) Repeat the situation again, this time taking screenshots to document exactly what is going on.

I do not doubt that you experienced an oddity, yet your description is insufficient to even begin to try to nail down what happened, much less devise a solution.