Hi Safiya,
From the Bode plot it is clear that the gain margin of your system is infinite and phase margin is about 100 degrees. Both of them are positive indicating a stable system. However, whether the system is stable or not cannot be directly inferred from the step response plot as your input step value is not clear.
Can you confirm if you are providing a unit step input? Can you please tell what is the step value?. Also the pole seems to be very close to imaginary axes, can you provide the pole zero locations?
-Mayank
