The economic term for a period of falling inflation rather than falling prices is disinflation. During disinflation, prices continue to rise, but they rise more slowly than before.
For example, if inflation falls from 8% to 3%, the economy has experienced disinflation. The general price level is still increasing, but the rate of increase has weakened. This differs from deflation, which means that the general price level is falling.
Central banks may seek disinflation when inflation is too high. They can raise interest rates or otherwise tighten monetary conditions to reduce demand and bring price growth closer to target. The process can also slow economic activity and raise unemployment.
Disinflation is sometimes confused with cheaper goods. A slowdown from 8% inflation to 3% inflation does not reverse earlier price increases; it only reduces the speed of future increases.