The Singular Name is not retrieved after saving

When a new custom post type is created, the choosed Singular Name (A singular descriptive name for the post type. e.g. Movie) is saved in the database, but is not retrieved again after saving, so the form field becomes blank. This means that, if the user is not careful about this, after the next saving the original Singular Name is rewritted (deleted) because of the blank Singular Name field.

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