Please download enhanced voices again when you restore your iPhone or iPad on iCloud or iTunes.
On your Voicepaper voice settings, you can check enhanced voices you downloaded before, but they are not in your devices when you restore your iPhone from iCloud or iTunes. Therefore, when you play texts, it will skip them right away before you hear anything.
Download Enhanced Voices from iOS Settings -> General -> Accessibility -> Speech -> Voices. After that, select an enhanced voice in the Voicepaper Settings -> Voice -> Language you choose.