It’s a life circle. Having purpose does not last forever. If we already have a purpose, it will dissolve one day. Then we have to be prepared to find a new purpose and keep growing.
Your purpose may dissolve. If this happens, go for a retreat with yourself, and the answer will come to you.
When you feel like your work is not aligned with your purpose anymore, the worst thing you can do is to look for gratification by watching TV, playing games, or dating a bunch of women.