1.power the box ...
2.remove the one the turner from the slot....
3.reboot the box...
if the tuner find after you reboot ....power of box again install 2th tuner and boot....like this u will verified if theres any damage tuner or software issue..
good luck
is it an original or a clone, if clone what sim is in it
images are here http://www.sat-universe.com/showthread.php?t=249356
estar home here h**p://www.e-star-sim.com/en/down-sim800se.php?tnid=4