Shortcode to force category not working

I am using [anspress question_category=””] I have created a category call “ESP8266 Module” with a slug of ans-esp8266-module and have tried:

[anspress question_category=”ESP8266 Module”]

and

[anspress question_category=”ans-esp8266-module”]

and neither work, I just get questions/answer for all and not the specific category.