Stop changing the affected item while support checks what happened. Please do not reset the episode or regenerate over the missing version.
First confirm that you are in the intended Mochi account, series, and episode. Similar titles or reordered scenes can make it easy to open the wrong item.
Then contact Profile → Support with:
Which item is missing or overwritten, and where it belonged.
When you last saw the correct version, plus a screenshot if you have one.
Tell us if you created new work after the problem started, so the team knows what needs to be preserved. If an earlier repair has reverted, say that in the same support conversation.
If only a scene take changed and an earlier take is still listed, check its Versions. Scene Versions do not guarantee recovery of a missing character card or deleted episode.
Support will check what is available. Recovery cannot be confirmed until the affected data has been reviewed.