Most likely, you need to refresh your device’s connection to YouVersion’s servers.
1) Home screen: Tap Bookmarks.
2) Press the Load More button or the refresh circle at the top right. Your device resyncs with YouVersion, downloading your bookmarks.
Note: Bookmarks download to your device in increments of 25 at a time. If you have a lot of bookmarks, allow the first group to completely download before you tap Refresh again. If you tap Refresh too rapidly, your connection may time out.