Cannot Connect To Mail Server With Port 587

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Server certificate
subject=CN = myhiddenserver

issuer=C = US, O = Let’s Encrypt, CN = R3


No client certificate CA names sent
Peer signing digest: SHA256
Peer signature type: ECDSA
Server Temp Key: X25519, 253 bits

SSL handshake has read 4435 bytes and written 424 bytes
Verification: OK

New, TLSv1.3, Cipher is TLS_AES_256_GCM_SHA384
Server public key is 256 bit
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
Early data was not sent
Verify return code: 0 (ok)

250 CHUNKING