I think this is an error with the version of one or more of your perl modules. (There's a discussion on github here: https://github.com/openwebwork/webwork2/issues/567.) The diagnosis there was that the version of LWP::Protocol::https that shipped with WeBWorK server's operating system (CentOS, in that case, so it likely applies to RedHat as well) wasn't sufficiently up to date. The solution there was to uninstall it with the operating system's package manager and then reinstall from CPAN.
I've found that I needed to upgrade a number of packages to get things working recently: SOAP::Lite and XMLRPC::Lite as well.
Gavin
WeBWorK Main Forum
Problem with Library Browser
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