Immigration to USA from Bangladesh under sibling category. help!?

my aunt stays in US. She applied for her siblings like 10 years ago. We got papers from the emby as they wanted our birth certificate and marriage certificate etc. then after checking them they were supposed to take an interview. My aunt who is the petitioner called the immigration center about how long will it take and they said that they are trying to find an interview date for us. do u think they really are trying to find an interview date or just making an excuse? do they actually make excuse? How long do u think it'll take to get visa? Its already been 2 months that we gave all our doents to them. still no interview date.