the command "bitcoin-cli getblockstats 0000000000000000000c61ff8f761ce509fc8901d3c22d61fec89637042ea2ba" does not work.

It displays "error: Error parsing JSON:0000000000000000000c61ff8f761ce509fc8901d3c22d61fec89637042ea2ba"

but it should display the block stats like the documentation says.

also bitcoin-cli getblockstats 0 does not work. block number must be at least 1 to work. But blocks start at 0.

tested with 0.20.1 on freebsd, another user on IRC acknowledged the problem.
{
    DISCONNECT_OK,      
    DISCONNECT_UNCLEAN, 
    DISCONNECT_FAILED   
};
class ConnectTrace;
enum class FlushStateMode {
    NONE,
    IF_NEEDED,
    PERIODIC,
    ALWAYS
};
/**
 * A convenience class for constructing the CCoinsView* hierarchy used
 * to facilitate access to the UTXO set.
 *
 * This class consists of an arrangement of layered CCoinsView objects,
 * preferring to store and retrieve coins in memory via `m_cacheview` but
 * ultimately falling back on cache misses to the canonical store of UTXOs on
 * disk, `m_dbview`.
 */
class CoinsViews {