New Category Error

I'm getting the following error when trying to add a new category.

[quote][font=Courier][size=3]Database error:[/size][/font][color=#000000][font=Tinos][size=1] Duplicate entry '196-EN' for key 'PRIMARY' [/size][/font][/color]b[/b]

[font=Courier][size=3]Invalid query:[/size][/font][color=#000000][font=Tinos][size=1] INSERT INTO cscart_category_descriptions (category, description, page_title, meta_description, meta_keywords, category_id, lang_code) VALUES ('Test Cat', '', '', '', '', '196', 'EN')[/size][/font][/color][/quote]

However when I go to 'categories' I find a new category has been created with an odd name like 'Cameras' or 'DVD Players

I've not added categories in a while but it previously worked without issue.

Cart Version: [color=#282828][font=arial, verdana, tahoma, sans-serif][size=3]3.0.4[/size][/font][/color]

Looks like demo categories were not deleted correctly. Please log in the phpMyAdmin and run the following query:

DELETE FROM cscart_category_descriptions WHERE category_id > 196;

Also please make database backup at first, just in case