Confusion in testing RPC and curl #28382

Please forgive the ignorance of a beginner.

I started a test network (bitcoind -testnet rpcuser=zz)

When I runbitcoin-cli -testnet getbestblockhash, everything works fine and I get the correct message, but when I run curl --user zz --data-binary '{"jsonrpc": "1.0", "id": "curltest", "method": "getbestblockhash", "params": []}' -H 'content-type: text/plain;' http://127.0.0.1:18332/

And I can't get any feedback.

Can anyone help me with the reason for this?

Is curltest necessary to change "id":"curltest" if I am starting the main network (bitcoind rpcuser=zz)?

Should I follow the port shown at https://developer.bitcoin.org/reference/rpc/getbestblockhash.html for the run, or should it depend on what I'm running on?

You'll have to pass the cookie password from the .cookie file, or create an rpcauth user-password pair via the rpcauth.py helper script. See also the help bitcoind -help (-rpcauth and -rpccookiefile)

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