recidivate, relapse, retrogress, regress, lapse, fall back - go back to bad behavior; "Those who recidivate are often minor criminals"

change by reversal, reverse, turn - change to the contrary; "The trend was reversed"; "the tides turned against him"; "public opinion turned when it was revealed that the president had an affair with a White House intern"

resile - return to the original position or state after being stretched or compressed; "The rubber tubes resile"

recuperate, recover, go back - regain a former condition after a financial loss; "We expect the stocks to recover to $2.90"; "The company managed to recuperate"

mutate - undergo mutation; "cells mutate"