instead, it adds a NOT segwit address to me.
how to get the correct one?
It's important to note that Blockchain.com is a web wallet and is not the best way to access your bitcoin address as there is a risk of accidentally landing on a phishing site and losing your funds. As recommended by OmegaStarScream and Charles-Tim, the Electrum wallet is a much safer solution.
However, if you still want to use a web wallet, you can try Bitamp Wallet. Bitamp is an easy-to-use, client-side, open-source Bitcoin wallet that also supports native SegWit addresses.
https://www.bitamp.com/
Official thread: https://bitcointalksearch.org/topic/bitamp-bitcoin-web-wallet-send-receive-bitcoin-instantly-5254736