1999 Toyota Corolla Starting problem

1999 Toyota Corolla 4 cyl Automatic 121000 miles

When I crank for starting car, firstly it didn't move to starter, means only knock sound appears. No movement in the starter motor. My battery is fine. After some attempt If got connection to starter, some movement in starter and car starts. But not sure why it knocks in first few attempts. THe longer car is unused(some hrs), chances are high facing this knocks.

I thought it would be corrosion, but my headlights, radio, and other stuff is working fine(even before start). NO message on the display also.

Regards