when i create a new post it just edits/overwrites old post

Hi, im decently new to wordpress and started running into a major problem when i try to add new posts to my website. First I will say that i was using different plug ins but i have since de-activated all of them and the problem has continued.

When I add a new post it brings me to a new page and I am able to do everything normally. But when i hit save draft or publish, the url link for the post changes to the url of a previous post. and when I return to my post list in my dashboard the new post is there, but it has just replaced the former most recent post.

I did some research to try and fix the problem and one solution was that I should clear my google cache/cookies. And this DOES WORK. but only once. if i do this i am able to add 1 new post, but any posts after that default to the same problem. Im hoping to find a way to add new posts to my site without clearing my cache every single time. Thanks!

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