Most probably CPANTS databases are being regenerated from scratch due to major changes in Kwalitee metrics or updates of relevant modules/perl. Usually this maintenance takes about a day or two, and some of the information may be old or missing tentatively. Sorry for the inconvenience.
No Core Issues.
If you are using Build.PL define the {requires}{perl} = VERSION field. If you are using MakeMaker (Makefile.PL) you should upgrade ExtUtils::MakeMaker to 6.48 and use MIN_PERL_VERSION parameter. Perl::MinimumVersion can help you determine which version of Perl your module needs.
Add a META.json to the distribution. Your buildtool should be able to autogenerate it.
Add all modules contained in this distribution to the META.yml field 'provides'. Module::Build or Dist::Zilla::Plugin::MetaProvides do this automatically for you.