If you haven't claimed your podcast on Spotify yet, go to podcasters.spotify.com and create an account and claim your podcast.
If you have already claimed your podcast on Spotify in the past, simply login to your account and replace the old RSS feed with your now new podcast RSS feed.
If your podcast was previously distributed to Apple podcasts, that would mean you would have already made an account at iTunes connect.
Simply sign in and update your old podcast RSS feed with your now new RSS feed.
This will notify both platforms that you have a new RSS feed generated for the same podcast which you had previously distributed.