Change Permlink on single post not taking effect

So I have this problem where I cannot change the permlink on a post.

I go into edit post, click on the edit button next to the permlink, change it and click on save and all appears well in the world.. However when I refresh the edit page it instantly goes back to the original permlink.

clicking on ‘view post’ after changing the permlink simply results in a 404 error but of course when I refresh the page and the permlink reverts back to the original the view post link takes me there just fine, albeit to the old unchanged url.

On a related note is there any way to get wordpress permlinks to work on the slug tag that you can edit in the quick edit window?

Thanks in advance for your help