How did Rome recapture Capua despite Hannibal’s attempt to relieve the siege?

In 211 BCE, Rome successfully recaptured Capua by maintaining a persistent blockade despite Hannibal’s attempts to intervene.12

When the Romans placed the city under siege in 212 BCE, they effectively resisted efforts by Carthaginian forces to break the encirclement. In a final attempt to relieve his allies in 211 BCE, Hannibal marched to within 3 miles (5 km) of Rome itself, intending to create a diversion that would force the Roman armies to abandon the siege. However, the Roman besiegers refused to be drawn away from their entrenchments. Consequently, the city was starved into surrender, marking a decisive failure for the anti-Roman coalition in Italy.21