Search Function on Backend not working Properly

I’m having a problem with a certain word on my website. If a URL on my website his the word “face” in it the page goes to a 404. if I change the permalink and remove the word “face” it goes to the correct page. Also in the wp admin area when I search for a phrase with the word “face” in it, it wont search it will just keep up with the loading indicator. But as soon as I change to a phrase without the word “phrase” it instantly responds. I’ve disabled all the plugins and also changed back to the 2011 theme to make sure those were not the problem. Any help would be greatly apprecaited

PS: I have around 20,000 posts and 800 pages on my site (just extra information)