Why did the Romans need a navy in the first Punic War? Why did they not need him in previous wars?

The military confrontation between Rome and Carthage went down in history under the name “Punic Wars”.

In the First Punic War, the Romans needed a navy, since Carthage was in North Africa, and the first Carthaginian attack took place in Sicily. The Roman fleet was supposed to cut off the army of Carthage from the main forces, which were concentrated on the mainland. And then with the help of the fleet, the Romans landed in Africa and began to advance inland.

Subsequent wars took place on land, so the need for a strong fleet disappeared, since the main burden fell on the ground forces.