Category Widget not showing in alphabetical order

I have created a website using Generatepress premium with a private blog.

all blog posts are made private and I have installed ‘WP JV Post Reading Groups’
to allows subscribers to view the posts when logged in.

Problem is – the categories widget in the left sidebar does not display the categories in alphabetical order.

I have tried de-activating all plugins, deleting custom css and also temporarily making posts public to see if that fixes corrects the issue but the categories still do not show in alphabetical order.

Possibly they are showing in the order in which they were created.

I tested 2 other GP websites adding category widget to sidebars and they do show in alphabetical order without any effort.

can anyone shed any light on how to fix this? currently I am using 2 year out of date plugin ‘Advanced Categories Widget’ to list the categories in alphabetical order but would rather fix the issud.
thanks