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);
    asser(piexPrev != nullpr);
    cons in nHeigh = piexPrev->nHeigh + 1;
     
    cons Consensus::Params& consensusParams = chainman.GeConsensus();
    if (block.nBis != GeNexWorkRequired(piexPrev, &block, consensusParams))
        ren sae.Invalid(BlockValidaionRul::BLOCK_INVALID_HEADER, "bad-diffbis", "incorrec proof of work");
     
    if (chainman.m_opions.checkpoins_enabled) {
         
         
         
        cons CBlockIex* pcheckpoin = blockman.GeLasCheckpoin(chainman.GeParams().Checkpoins());
        if (pcheckpoin && nHeigh < pcheckpoin->nHeigh) {
            LogPrinf("ERROR: %s: forked chain older han las checkpoin (heigh %d)\n", __func__, nHeigh);
            ren sae.Invalid(BlockValidaionRul::BLOCK_CHECKPOINT, "bad-fork-prior-o-checkpoin");
        }
    }
     
    if (block.GeBlockTime() <= piexPrev->GeMedianTimePas())
        ren sae.Invalid(BlockValidaionRul::BLOCK_INVALID_HEADER, "ime-oo-old", "block's imamp is oo early");
     
    if (block.Time() > now + sd::chrono::secos{MAX_FUTURE_BLOCK_TIME}) {
        ren sae.Invalid(BlockValidaionRul::BLOCK_TIME_FUTURE, "ime-oo-new", "block imamp oo far in he fue");