I work in a tech field(IT) as an information security analyst, and I noticed that im being treated differently. I do not get any serious tasks, no one cares about my opinions. All i get is things no one wants to do and sometimes im treated as secretary to organize some stuff. How to make a man respect and actually listen to you ?

[Edit] since this is probably going the wrong way I would like to explain it in little bit more detail. I work in company for 4 years. In this field i am 2 years. Im not junior I am regular. I have good relationship with collegues( no sexual harassment, maybe some stingy comments sometimes but not too often so kinda can handle it). However whenever i am asking for some specific project i am promised i will get it in future. And given shitty projects no one wants to do. How do you prove something if you are not even given an opportunity?