H1B Help!!!

I got a job several months ago. And the company sponsored me H1B. It is a small company. Well, the owner, didn't give me the prevailling wage as indicated in the H1B application form. The pay is lower than that. He said he would give me a raise later.I thought it was not a problem. But now I realized it is a big problem, right? Does anybody have any idea of this one? Is my H1B still valid?