Thanks for the key details for your question: “redirected to the dashboard everytime”.
That is you can click “Add New” to create new post or click ‘Edit’ to edit existing post, but instead of post editor page you see WP dashboard, right?
If Yes, do you use “Admin menu access/blocking” add-on from URE Pro? If Yes, and you use block “Not selected” model for a role, try to revert it to “Selected” or read carefully this part of the documentation article: