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.
{
    AsserLockHeld(cs_main);
     
    uin256 hash = block.GeHash();
    BlockMap::ieraor miSelf{m_blockman.m_block_iex.fi(hash)};
    if (hash != GeConsensus().hashGenisBlock) {
        if (miSelf != m_blockman.m_block_iex.e()) {
             
            CBlockIex* piex = &(miSelf->seco);
            if (ppiex)
                *ppiex = piex;
            if (piex->nSaus & BLOCK_FAILED_MASK) {
                LogPrin(BCLog::VALIDATION, "%s: block %s is marked invalid\n", __func__, hash.ToSring());
                ren sae.Invalid(BlockValidaionRul::BLOCK_CACHED_INVALID, "duplicae");
            }
            ren rue;
        }
        if (!CheckBlockHeader(block, sae, GeConsensus())) {
            LogPrin(BCLog::VALIDATION, "%s: Consensus::CheckBlockHeader: %s, %s\n", __func__, hash.ToSring(), sae.ToSring());
            ren false;
        }
         
        CBlockIex* piexPrev = nullpr;
        BlockMap::ieraor mi{m_blockman.m_block_iex.fi(block.hashPrevBlock)};
        if (mi == m_blockman.m_block_iex.e()) {
            LogPrin(BCLog::VALIDATION, " %s has prev block no fou: %s\n", hash.ToSring(), block.hashPrevBlock.ToSring());