Expected that 6 tags limit is set on the field "Enter tags". Apparently 2 tags are already in (category/subcategory) and 1 is for the game name (I'll call it domain). So essentially it's 3 custom tags allowed for user to pick. Would be nice to improve the user experience either with: 1) tags count remaining on ui 2) updating limit to 3 and validate only custom tags entry 3) identifying currently taken tags in the error prompt 4) your vision on how to fix the frustration when you enter tag, it asks 6 and you trying to pin-point what are those tags. I'd prefer option 1. Many thanks for considering this inquiry.
This sounds like something that might be good to have tagged in #Feedback over Offtopic. Might help it get to the right people.