Hi,
The category names, like the product names and many other fields in HikaShop support translation overrides.
So in these fields, you can enter a translation key and Joomla will convert it to the corresponding translation if it's available in the translation files loaded on the page.
And it just so happens that HikaShop has a translation key:
AFRICA="All of Africa"
in its translation file (which contains all the text used on the interfaces of HikaShop):
www.hikashop.com/component/updateme/down.../language-en-GB.html
So it's conflicting with your category name.
What you can do to circumvent that is to enter something like this in your category name:
MY_AFRICA_TRANSLATION_KEY
And then, edit your translation file under the "Languages" tab of the HikaShop configuration and add in the override area on the right side:
MY_AFRICA_TRANSLATION_KEY="Name I want for my category"
www.hikashop.com/download/languages.html#modify
That way, on your frontend, you'll get "Name I want for my category" for that category.