You can only have 5 tags, if you go to your Neocities profile you'll be able to add/remove tags (but the "add" option only appears if you have less than 5, so you have to remove some first)
A tag can only be a single word, and can only contain letters and numbers.
Select the tags you would like to remove:
You are going to block this site. This will do the following:
Are you sure you want to do this?