Billy,
Most insurance companies have a cooling off period of 14-28 days where you can cancel your insurance contract. If that does not apply in your brother's situation, then he can always contact the insurance company and inform them about his
driving ban. They will surely understand that since he will not be allowed to drive, he does not need the insurance cover anymore.
Some insurers may charge an administration fee for this along with however many days insurance cover they provided until they were informed of the change in circumstances.
