Anyone know Wiltel's EWAN service

I have EWAN circuits of Wiltel(currently same company with Level3 you know) as my backbone circuit in LA.
About 2 months ago, there were some packet loss on L2 circuit, but I didn't get any clear answer from Level3 support center.
It became okey without any action, but now, same problem happen again. I feel bored, I need your help.
Anyone know if there are any problems of WilTel's L2 circuit on LA area ? or
Could anyone advice me the contact person who know well EWAN configuration of Wiltel ?
Frankly, I felt Level3 guys seems to be unfamiliar with EWAN circuit of Wiltel.

Best regards,