You need to check all of your libcurl and openssl components. curl 7.61 and 8.7.1 both support tls 1.2.
curl -V
curl 8.7.1 (powerpc-ibm-aix7.1.5.0) libcurl/8.7.1 OpenSSL/1.1.1v zlib/1.2.13 libssh2/1.10.0 nghttp2/1.58.0 OpenLDAP/2.5.16
It does connect via tls 1.2:
curl -s --tlsv1.2 -d
With no issues.
Try connecting to your server with openssl:
openssl s_client -connect hostname:443 -tls1_2
or
openssl s_client -connect hostname:443 -tls1_3
If you see a section about:
Post-Handshake New Session Ticket arrived:
SSL-Session:
Protocol : TLSv1.3
(search for Protocol)
Then you connected and received a ticket.
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James Lohman
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