After starting a premium dungeon, the reward is superimposed over the text (after Begin Adventure). Might be a known issue, but guess the lack of premium dungeons with flavour text is quite low, so haven't noticed it myself before. Noticed on Temple of Scales (which has flavour text), but seems to persists on other - even if they're only [null] textwise. Heading out and back in again, makes the item not be shown as shoule be. But leaving an adventure and returning causes it to repeat.