I tried to change the category of a Topic which is not pinned or archived or any of that.
When I try to save the change it just resets to the same old category. I tried multiple other categories and it won’t work.
Any assistance will be appreciated please.
Hello!
Is it a Discourse’s default category or topic?
There’s only one topic in your category, but Discourse always creates a “About this category” topic by default. This topic can’t be deleted or moved to another category.
My guess is that you renamed and unpinned this default topic. 
You can be sure of that by checking the first post’s edit history. The first version should have some placeholder text including:
(Replace this first paragraph with a brief description of your new category. This guidance will appear in the category selection area, so try to keep it below 200 characters.)
Understood. Will do thank-you.
