You’re stuck with Verizon for 36 months as the credits to make it free are spread out over 36 months. You also have to be on the specified Unlimited plan.

A free phone is typically a massive red flag. A base iPhone 15 Pro Max is $1750+tax. No company would give that kind of device for free.  The caller not having your details is another massive red flag, as is calling from local numbers of any kind. The scam is targeting Canadians in general right now and not just Telus customers. Part of the scam is that if they get the info and account pin, after changing your contact details they'll order a phone (or multiple) and ship it somewhere else to re-sell them. They'll send a fake email making it look like a phone is being shipped to you but it would never arrive. Those unfortunate enough to fall victim to the scam likely would have no idea until their next billing cycle when they get charged for the new phone(s) and plan to go with it.