Is my kids' mom allowed to deny me my rights to my children?

I am being denied my rights to my kids. I seen a court appointed advocate for my children for like 6 months. But I did get in trouble for drugs a yer and a half ago. But I have been clean for over a year and I have went to counseling, taken drug test through DCS and have gotten back full custody of my daughter through a different relationship. I have not seen my 2 kids in over a year and a half because there mother won't let me. The court appointed advocate wrote a letter to the judge to dismiss her self from the case, and there mother still won't let me see my kids. I have wrote the judge 3 times asking for a court hearing to get this matter resolved and it's been 3 months and still have t heard anything from the judge. I can't afford a lawyer, but do pay my child support, what do I have to do to see my children?