Pjiang or other Da Xia Please help with "returned notice - undel

I have never changed my address and have received EAD and FP notice at my home address. My AP was mailed to my lawyer's address. But my online status is "returned notice - undelivable". I called TSC, the lady told me she could not see my address nor she could tell me what the notice is. All she could do was to request mail again. I saw an update after that call. But so far I have not received any notice. I know that another call might be still no help.

Should I fax TSC or write a letter to them? Could you please let me know what the fax number or mailing address I should use. Thank you very much!