SSL connection failure: A packet with illegal or unsupported version was received.

Hi!

my OpenConnect version v8.10

Using GnuTLS 3.7.2. Features present: TPM, TPMv2, PKCS#11, RSA software token, HOTP software token, TOTP software token, Yubikey OATH, System keys, DTLS, ESP
Supported protocols: anyconnect (default), nc, gp, pulse

on Linux fedora 5.12.8-300.fc34.x86_64 #1 (closed) SMP Fri May 28 15:20:54 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

and then i try to connect vpn i have answer

$openconnect vpn.server.ru 
POST https://vpn.server.ru/
Connected to ip_my_server:443
SSL negotiation with vpn.server.ru
SSL connection failure: A packet with illegal or unsupported version was received.
Failed to open HTTPS connection to vpn.server.ru
Failed to obtain WebVPN cookie

for gnutls-cli-debug i have:

$gnutls-cli-debug vpn.server.ru
GnuTLS debug client 3.7.2
Checking vpn.sewrver.ru:443
whether the server accepts default record size (512 bytes)... no
                  whether %ALLOW_SMALL_RECORDS is required... no
                        whether we need to disable TLS 1.2... yes
                             for TLS 1.2 (RFC5246) support... no
                             for TLS 1.3 (RFC8446) support... no
                    for known TLS or SSL protocols support... no

How can i connect to this server from my workstation&