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[nVault Array] Can only use nvault_get_array() on data that was saved using nvault_set_array().
Based on the error it looks like you may have already stored data in string format under the same vault file and key for the player. When nvault_array attempts to load the data, it finds a string instead of the nvault_array-formatted data so it throws the error. If using nvault_array on a vault file that was previously used with nvault_set(), you must prune everything or use a new vault file.
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