I sounds like something went wrong. If you are waiting this long it might be because you applied for LPR through employment or through a family member other than parents. It usually takes about 10 years for both items I listed, however if you applied through marriage to a citizen or LPR, then you should use your receipt number and contact uscis.gov to find out where you are at in the application process. Or you can contact www.emichoice.com and someone will assist you for free. I hope I was helpful.