You're certain it's Credit One and not some other company with similar name. Seems very odd Credit One would be calling to reopen a closed card.
Based from what I've read on the forums here, generally when one cancels Credit One, that's it. If they've not retained the customer during the cancellation call, that's the end of the matter ... well, other than extra fees, but your account shows zero, so that shouldn't be an issue.
Maybe they're calling regarding the 1% back on gas and groceries (new) you're missing out on 
@Anonymous wrote:Credit One is a very annoying bank. They offer cards with low CL and high APR because they know that people with lower scores will keep the card, just happy to get credit. That itself isn't neccesarily bad. There is a need there, and they fill it.
The problem is that their "Credit Analysts" are actually just a sales team that is hellbent on keeping you with them forever (gotta get that big annual fee, plus who knows maybe you will slip and have to pay the 29% APR). I would imagine when you called to cancel they spent a good bit of time trying to talk you out of it?
My suggestion would be to do the no call list (which you did) as the other person said give them 30 days to update you to the list. If after that point, they are still calling and you have made multiple requests to stop, make a BBB complaint. They are required to resolve it within 30 days with a "reasonable conclusion" and they will just leave you alone from there.
Actually they can call up to 18 months post closing out their card per FTC rules
https://www.donotcall.gov/faq/faqbusiness.aspx#who
Who May Or May Not Call? Who Is Covered By The National Do Not Call Registry?
The National Do Not Call Registry applies to any plan, program, or campaign to sell goods or services through interstate phone calls. This includes telemarketers who solicit consumers, often on behalf of third party sellers. It also includes sellers who provide, offer to provide, or arrange to provide goods or services to consumers in exchange for payment.
The National Do Not Call Registry does not limit calls by political organizations, charities, or telephone surveyors.
For more information, please see FTC INFORMATION AND DOCUMENTS below.
What About An Established Business Relationship?
A telemarketer or seller may call a consumer with whom it has an established business relationship for up to 18 months after the consumer's last purchase, delivery, or payment - even if the consumer's number is on the National Do Not Call Registry. In addition, a company may call a consumer for up to three months after the consumer makes an inquiry or submits an application to the company. And if a consumer has given a company written permission, the company may call even if the consumer's number is on the National Do Not Call Registry.
One caveat: if a consumer asks a company not to call, the company may not call, even if there is an established business relationship. Indeed, a company may not call a consumer - regardless of whether the consumer's number is on the registry - if the consumer has asked to be put on the company's own do not call list.
For more information, please see FTC INFORMATION AND DOCUMENTS below.
@Anonymous wrote:You're certain it's Credit One and not some other company with similar name. Seems very odd Credit One would be calling to reopen a closed card.
Based from what I've read on the forums here, generally when one cancels Credit One, that's it. If they've not retained the customer during the cancellation call, that's the end of the matter ... well, other than extra fees, but your account shows zero, so that shouldn't be an issue.
Maybe they're calling regarding the 1% back on gas and groceries (new) you're missing out on
I'm very certain its them because I called the number back and sure enought it was Credit One. I came in to work this morning and had 4 missed calls. Sure enough they were all from Credit One. I'm going to figure out how to block their number. I'm sure they will probably call me from a different number.