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.
{
    return RPCHelpMan{"verifychain",
                "\nVerifies blockchain database.\n",
                {
                    {"checklevel", RPCArg::Type::NUM, RPCArg::DefaultHint{strprintf("%d, range=0-4", DEFAULT_CHECKLEVEL)},
                        strprintf("How thorough the block verification is:\n%s", MakeUnorderedList(CHECKLEVEL_DOC))},
                    {"nblocks", RPCArg::Type::NUM, RPCArg::DefaultHint{strprintf("%d, 0=all", DEFAULT_CHECKBLOCKS)}, "The number of blocks to check."},
                },
                RPCResult{
                    RPCResult::Type::BOOL, "", "Verified or not"},
                RPCExamples{
                    HelpExampleCli("verifychain", "")
            + HelpExampleRpc("verifychain", "")
                },
        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
{
    const int check_level{request.params[0].isNull() ? DEFAULT_CHECKLEVEL : request.params[0].getInt<int>()};
    const int check_depth{request.params[1].isNull() ? DEFAULT_CHECKBLOCKS : request.params[1].getInt<int>()};
    ChainstateManager& chainman = EnsureAnyChainman(request.context);
    LOCK(cs_main);
    Chainstate& active_chainstate = chainman.ActiveChainstate();
    return CVerifyDB().VerifyDB(
        active_chainstate, chainman.GetParams().GetConsensus(), active_chainstate.CoinsTip(), check_level, check_depth);
},
    };
}
static void SoftForkDescPushBack(const CBlockIndex* blockindex, UniValue& softforks, const ChainstateManager& chainman, Consensus::BuriedDeployment dep)