Need advise on how to update the name on my alien reg. no.

[moondream 36]

Hi! I came to U.S thru K1 visa. AOS: Aug.6, 2013, EAD: approved 10/10.

Aug.2013, i applied for driving permit and passed but the expiration is only till sept 10. (based on I-94 expiration) Now that my EAD is approved I went to DMV, Ft. Collins, CO., to renew my driving permit. I presented my ID and proof of current address everything was fine but when the lady checked my EAD card with Alien no. on it. she said, it didn't match. According to her my Alien Registration no. is still on my Maiden name and was told to call USCIS to update my record. I called uscis, (First call) the customer svc rep said that i need to have a infopass,to talk to Immigration Officer. (2nd call, waited 3hrs) tier 2: says my name is updated on their system. so im confused! I called again waited 3hrs again. she said shes tier 2 but she doesn't have access on my record and told me to get infopass like the advised of the customer svc not the other tier2... Now im doubting if shes really Tier 2 .....

My Question is, how can i update my name on uscis record from my maiden to married name?

Thank you so much!