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.
{
    
    
    
    std::pair<uint256, DBVal> read_out;
    if (!db.Read(DBHeightKey(block.height), read_out)) {
        return false;
    }
    if (read_out.first == block.hash) {
        result = std::move(read_out.second);
        return true;
    }
    
    
    return db.Read(DBHashKey(block.hash), result);
}
std::optional<CCoinsStats> CoinStatsIndex::LookUpStats(const CBlockIndex& block_index) const