I cannot create or edit categories in my Google Plus community.
Something is wrong I could do this before. No settings have changed and everything remains the same.
Yes, I do have a source, I am the owner of two communities on Google plus. I creating another community to test my hypothesis that there is a limit to the number of categories you can create and found that there is. Once you exceed this limit you cannot edit or delete any of these categories.
There should be advice on how many categories you can create, the number I arrived at was 16 add another and you have exceeded the number and cannot bring the number back down so that you can edit or change them in any way that I know of.
You can add up to 17 categories to G+ any more and you can't edit, add or change them. That is the limit that you can have.