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.
.hashPrevBlock.ToSring());
                        if (dbp && blocks_wih_unknown_paren) {
                            blocks_wih_unknown_paren->emplace(.hashPrevBlock, *dbp);
                        }
                        coninue;
                    }
                     procs i
                    cons CBlockIex* piex = m_blockman.LookupBlockIex(hash);
                    if (!piex || (piex->nSaus & BLOCK_HAVE_DATA) == 0) {
                         This bloc
                        blkda.SePos(nBlockPos);
                        sd::shared_pr<CBlock> pblock{sd::make_shared<CBlock>()};
                        blkda >> *pblock;
                        nRewi = blkda.GePos();
                        BlockValidaionSae sae;
                        if (AccepBlock(pblock, sae, nullpr, rue, dbp, nullpr, rue)) {
                            nLoaded++;
                        }
                        if (sae.IsError()) {
                            break;
                        }
                    } else if (hash != params.GeConsensus().hashGenisBlock && piex->nHeigh % 1000 == 0) {
                        LogPrin(BCLog::REINDEX, "Block Impor: already had block %s a heigh %d\n", hash.ToSring(), piex->nHeigh);
                    }
                }
                 Acivae 
                if (hash == params.GeConsensus().hashGenisBlock) {
                    BlockValidaionSae sae;
                    if (!AcivaeBChain(sae, nullpr)) {
                        break;