Having a lower inflation rate is not the same as having lower overall prices? Having a lower inflation rate is not the same as having lower overall prices.Why?

lower CPI(inflation) means price levels in country decreases?
The inflation rate is the rate of change in the price level. 

A lower - but positive - inflation rate (say from 3% to 2%) still results in higher prices -this is typically called disinflation, and highlights the fact that lower inflation doesn’t necessarily mean lower prices.

A negative inflation rate print (like -1%) implies the price level did actually decrease - typically referred to as deflation.