Wysiwyg editor not showing html button

I am facing a weird issue.

I have a field with type wysiwyg editor. At the beginning the html button/icon was missing.I couldn’t see the html button from a page which is a custom post type

The url is edit-tags.php?action=edit&taxonomy=product_cat&tag_ID=18&post_type=primo_product

But surprisingly I could see the html button here

edit-tags.php?taxonomy=product_cat&post_type=primo_product(Which is a category addition page)

Then I installed tinymce advanced plugin to make it more better than before. Now same again the tables and tool buttons are missing from the category edit page but not from category addition page. I have attached the screenshot so that you can understand.

With tool/tables buttons screenshot

Without tables/tool buttons screenshot

My wp version is 4.2.2. Is it something like overriding issue or to do anything with custom post type? Before installing tinymce advanced button the html icon ie <> was missing from edit page but was in category addition page.

Any help is highly appreciated. Thanks in advance.