Firstly you should tell the name of this casino, where you met 0% house edge, then definitely we will help you. Only tell us, it is not enough for us to guide you. But as far as i guess no one casino is here where you could play with 0% house edge.
So it is difficult for us to trust you, that you are right telling us or not. But still i will tell you try to test in this casino where 0% house edge then sure you will know about it.