You are a Plat with onepass and I am surprised that you are still waiting and counting on a response.
If it is truly significant then call them; send a letter to the CEO's office and to customer service. Write another e-mail and call the phone given earlier.
I have found that you have to attempt several contacts before something is actually done.
If it is not very significant (like the 500 miles they owe me from an Austrian flight) I just give up and try to forget about it (very hard to forget).