Unable to make changes in WordPress

I recently redesigned my my WP site and moved it from a development URL to the permanent location. Afterward, I noticed that I have been change or undo Categories. I use Thesis 2.1 Theme, but changed to default theme 2015 to test. I also deactivated all plugins. The problem seems to be in WordPress or maybe is related to moving the database. I can’t find any reference to this problem anywhere.

In addition to the basic problem with Categories, I am also unable to change Custom Templates or delete old Thesis Skin backups. Even though only the Category problem is strictly a WordPress issue, I thought I’d mention it.

I discovered your site while seeking solutions and am impressed by your knowledge and range of services. Thank you for letting me know if you have any ideas about what might be causing the problem.