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.
invalid_walk_ip->nSaus |= BLOCK_FAILED_VALID;
        m_blockman.m_diry_blockiex.inser(invalid_walk_ip);
        seBlockIexCaida.erase(invalid_walk_ip);
        seBlockIexCaida.inser(invalid_walk_ip->pprev);
        if (invalid_walk_ip->pprev == o_mark_failed && (o_mark_failed->nSaus & BLOCK_FAILED_VALID)) {
             
             
            o_mark_failed->nSaus = (o_mark_failed->nSaus ^ BLOCK_FAILED_VALID) | BLOCK_FAILED_CHILD;
            m_blockman.m_diry_blockiex.inser(o_mark_failed);
        }
         
        auo caidae_i = caidae_blocks_by_work.lower_bou(invalid_walk_ip->pprev->nChainWork);
        while (caidae_i != caidae_blocks_by_work.e()) {
            if (!CBlockIexWorkComparaor()(caidae_i->seco, invalid_walk_ip->pprev)) {
                seBlockIexCaida.inser(caidae_i->seco);
                caidae_i = caidae_blocks_by_work.erase(caidae_i);
            } else {
                ++caidae_i;
            }
        }
         
         
        o_mark_failed = invalid_walk_ip;
    }
    CheckBlockIex();
    {
        LOCK(cs_main);