why is this blogpost redirecting

It’s not redirecting for me. Try an incognito/private session in your browser.

See https://i.imgur.com/9oTLzQg.png

cookies issue with wordpress?

indeed when using incognito/private session. but now all my visitors need to do that or clear cookies.

what can I do to fix this?

If it’s a cookie thing, your visitors who had the issue will need to clear any cookies related to your site. As it didn’t happen for me, it does not affect new visitors to the site.

I just checked both url without redirection

some cashing issue… when you got the redirection, you keep getting the wrong link except for when you clear the cashe