When at a cruising speed (60) my car will decelerate randomly for a second

What is your question?

At cruising speed (60-70mph) the car decelerates for a about 2-3 seconds, the serpentine belt will squeal slightly and then the car catches up with a slight jump and is back at cruising speed. This doesn’t happen when i am accelerating or decelerating, only while cruising.

How long has your 2014 Chevrolet Spark had this problem?

About 2-3 months