Kind of odd longevity, you should have kept them alive well into their teens

Make shure you give them a big cage, lots of branches of non toxic wood, a nest would be good, protect them against air corrents and cold, dont feed them letuce, doble chek that toxic paint thing, give them regularity fruits like apple , dont expose them to insectisides and buy them from a local breeder not from a pet shop. OH and buy a good book about them. That should greatly increase your budgies life

Dont forget to select young healty birds and preferably get more than 2, 3 copples would be ideal. They are social animals, they need others to talk to like we need other people