It is been 2 weeks since USCIS received my N400 application packet and my check is not yet cashed. I am worried. Any suggestions on what to do? Call USCIS? If so, what number? Call and ask for what? Who do I ask to speak with? Is there anything I can do with the Post Office? I sent it via Express mail (waived signature required since I do not know if any USCIS employee would sign for it). Although Post office signed for it.