You cannot restore the deleted Cards

Please note that if a Card is deleted, it cannot be restored.

When deleting a Card, please make sure that it is really OK to delete it before taking action.

Unrecoverable Patterns

When a Card is deleted from the Note screen by placing it in the Trash box, etc.

When a note is deleted from the note list

Ways in which it may be possible to recover some data

If you removed the Card from the "Material Box", please remove it from the Material Box again.

If you have removed a card from the Material Box, please check the " Trash Box" in the Material Box.

If a Card has been "Send" or something similar, the history is still on the Timeline. Please retrieve it from the timeline.

If the Card is still in the "Submission Box", please remove it from the Submission Box.

Reference