Cognizant Technology Solutions — didn't receive the confirmation mail from cognizant after clearing all rounds

I was interviewed on 30th november at galgotias college of engineering, greater noida. I cleared the technical round, hr round also went smoothly, the hr asked me if i'm comfortable to relocate. I agreed and signed on the paper hr asked me. The hr then asked me to wait for one week that i would receive mail from them within a week. But it's been more than a month now but i've not received any mail from cognizant yet.