If you have just moved your show to Acast Open—congrats! You will have imported your show to Acast Open and will now have a new RSS feed URL.
All ordinary podcast apps (like iTunes, Overcast, Pocket Casts, Castbox etc) will automatically update your feed when you redirect from your previous podcast host. However, some non-traditional apps, specifically Stitcher and Google Play will require that you send them a note about this change.
Update your feed on Google Play
Sometimes Google Play does not update your feed even after you have redirected—especially if you just came from SoundCloud. To fix this, proceed to the Google Play Podcasts Portal and then contact Google Podcast Support requesting that they update your show with your new Acast Open RSS feed URL.