Marcel brought up in the comments that Verizon Media has a postmaster site. https://postmaster.verizonmedia.com/
The ex-AOL and Yahoo folks have done a great job providing information for senders to help troubleshoot their mail. There is a direct link to receive sender support. As I’ve said before, you should always use the form when looking for sender support.
Thanks to all the VM folks who have worked so hard to get a new postmaster site up and running with useful information.