re-entry after 5 year ban?

I got a 5 year ban under 212(a)(6)(c)(i) and 212(a)(7)(A)(i)(II). I (Canadian citizen) was going to US to overlook a business and got banned based on the papers i had, i was not aware if i needed some sort of visa. The five years are now over and i tried to enter US yesterday and provided all my ties to Canada with job letter, tax returns, bills and lease documents.

I was denied re-entry again. Reason as per the officer: 212(a)(6)(c)(i), can't enter as this states a life term ban, the notice that i received only said 5 years, the officer didn't buzz and returned me back and suggested to apply for advanced entry with I-192. My wife was with me as well and they had no objection on her entry to US. We were going to see my sister in law as her sister in law is getting married and we had the invitation.

Any suggestions? was the officer right saying that its a life time ban even though the "Notice and Order of Expedited Removal' says 5 years. Should i re-try entering US or apply for advance entry? will they have record of my yesterdays entry if try again from diff. port?

They'll have record of your recent denial yes, if they entered it to the computer (which they most likely did).

Maybe make an appointment at a US consulate close to you and speak with someone there a bit more knowledgeable. They may be able to suggest next steps for you. And they may be able to explain why the CBP told you you have been barred for life, rather than 5 years.