Immigration LOST My VISA! Help!

[iGaia]

My case has been going on for about 10 years already. Back in 2002 me and my family were detained at the Krone Detention Center in Miami FL. There they took all our documents (including VISAs) and they were supposed to keep them until 2007, when we received Asylum. After receiving our Asylum, they told us we had to contact USCIS to get our documents back. Months went by and we never received them. When my mother called back they claimed to have lost our VISAs during the process. Now that I turned 19, I am wanting to file for Permanent Residence and the I-485 has a lot of questions based on VISA. I do not have my VISA, immigration is to blame for, so what am I supposed to do now? Has anyone gone through this situation?

I scheduled an appointment with a local immigration office for next week. But I just want to know if anyone else has gone through this and what should I expect?