Crazy redirect happening with no redirects set up

In order to rule these out, I would first disable Redirections and Pretty Links, then make sure my htaccess file was the same as the default WordPress htaccess file. I see it’s a 301 redirect. Those get cached fairly hard, so make sure you clear your cache after these changes.

https://wordpress.org/support/article/htaccess/ or download a fresh copy of WordPress and get the htaccess file.