Lost phone covered by Apple care

I hate to give you the bad news, but you will be denied a replacement phone because Find My was required to be set up before the phone was lost. Apple will NOT replace the phone for you. Sorry.

You're going to have to purchase a new iPhone on your own.

Here are the exact words which validate what I just shared with you and the link to see it is below:

AppleCare+ with Theft and Loss

Get everything included in AppleCare+ and up to two incidents of theft or loss coverage every 12 months.3 Each incident is subject to the deductible listed below.

Theft and loss coverage requires you to have Find My enabled on your device at the time it is lost or stolen and throughout the claims process.

AppleCare Products - iPhone - Apple

As mentioned, because you didn’t have Find My set up your claim will be denied. It is a clear requirement in the terms for AppleCare+ Theft and Loss protection. Because you didn’t have it active you will be responsible for purchasing a new phone on your own. If you purchased the now stolen one with a credit card you can check and see if it offers any benefit that covers loss and theft but otherwise you’re going to have to replace your phone yourself