calling back this number (226) 663-8231 the same day the call is received and number not in service ,
what is this ?

do not call back or will make police complaint,
this is ILLEGAL to use a telephone number like this ...

Illegal robocall about credit card phishing. It is not legal in Canada to make unsolicited calls when the person is on the do-not-call list, and even without the list it is not legal to make robocalls at all, unless it's charity or by a political party.
226 area code is in Ontario. Either there is a company in Ontario making these illegal calls, in which case someone could sue them theoretically, or, it's some sort of phone switch. Either way, the company providing this phone switch, if that's what happening, could be held liable.
It's sad that there are people that can make a buck through dirty work like this. Phishing for people's financial status information. Not that they're looking to actually steal, but to log you in a database as a person to sell products to, like alternative credit cards and debt control services and whatnot. These types of companies build databases and sell these databases. It's all very scummy.

Same here.

This number called my cell phone while I was at a funeral. I didn't answer, but the display said "Ontario". I called back later and got a recorded message that this number is not in service.

I received this call today and I don't even own a credit card !! haha

I too got a call from this number telling me they can lower my intrest rate on my credit card but when I asked them what else they know about me that i was not aware of the man on the other phone hung up on me!  So much for curtesy....

Oh my!!! I just had the same thing happen to me.  He told me to f*ck o*f too after I asked him to provide more information and told him not to call here again.  I have to admit I was pretty shocked by his response, so my reply to him was a "same to you too":).  I have since filed a report with the anti-fraud website with the Government of Canada.  These are the scum of the earth...they pray on older adults and other trusting individuals. The government should come down harder on these people (that is saying it nicely).

I also got a call from this number from Eastern Ontario. Called it back. Not in service!