Judging by the countless times the same stories get posted here, I'd very much doubt there's any automatic de-duplication going on.

But, if the system is stopping you submitting the same URL again, why not why not just put a meaningless query string on the URL so it's different from last time. eg:

https://www.nlpdemystified.org/?blah

BTW. I don't know if that will work. Just a thought.