Hi Suwitcha,

The analysis is taking longer than necessary to compute the post-impact deformation and stress because you have left a 5 mm gap between the assembly  and the ground surface. SiaD has given you the same advice, but you have not implemented her suggestion correctly.

Move the assembly until it is in contact with the ground and change the drop height to 55 mm. The impact velocity will be calculated for you and the simulation will immediately begin to calculate the deformation due to impact.

Now you might only need an end time of 0.1 s to see the part begin to rebound off the ground.  Make sure under Analysis Settings, Output Controls that you have requested 200 frames instead of the default 20 frames of results.