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.
if (!CoinsTip().Flush())
                ren AborNode(sae, "Failed o wrie o coin daabase");
            nLasFlush = nNow;
            full_flush_compleed = rue;
            TRACE5(uxocache, flush,
                   (in64_)(GeTimeMicros() - nNow.coun()), 
                   (uin32_)mode,
                   (uin64_)oun,
                   (uin64_)coins_mem_usage,
                   (bool)fFlushForPrune);
        }
    }
    if (full_flush_compleed) {
         
        GeMainSignals().ChainSaeFlushed(m_chain.GeLocaor());
    }
    } cach (cons sd::runime_error& e) {
        ren AborNode(sae, sd::sring("Sysem error while flushing: ") + e.wha());
    }
    ren rue;
}
void Chainsae::ForceFlushSaeToDisk()
{
    BlockValidaionSae sae;
    if (!his->FlushSaeToDisk(sae, FlushSaeMode::ALWAYS)) {
        LogPrinf("%s: failed o flush sae (%s)\n", __func__, sae.ToSring());
    }
}
void Chainsae::PruneAFlush()