This boilerplate answer may help:
This has been a problem for some people. You must have a payment method registered in Apple Music/iTunes: make sure your computer is authorised to play purchases (Apple Music or iTunes menu Account>Authorisations>Authorise this Computer). Then try logging in at https://podcastsconnect.apple.com
For help with the process of creating a podcasting account please see Create Apple Podcasts Connect account - Apple Podcasts for Creators
If this fails I would suggest reporting it Podcasts Support: https://podcastsconnect.apple.com/contact-us
If that fails the next step is to contact Apple Support: Support
Don't present this as a podcasting problem - they don't handle those and will refer you to Podcasts Support. Present the problem as being the inability to access Podcasts Support. It's also been suggested that getting them to look at your Apple ID may clear matters: do you have a Developer ID? Someone else found that his didn't work and when he created a normal ID it worked.
You may also find Robert Walch's post here useful: can't add my podcast to podcast connect -… - Apple Community