Unauthorized Apple ID access after iPhone was stolen

No, no, and no to the three questions. The only way to get into your Apple ID was to guess your password. If you had your iPhone set to lock up after ten tries at entering your password that wouldn’t happen. If you didn’t then they could keep trying. There are sophisticated ways to break into an iPhone but common thieves do not have the means to do so. Only state actors , i.e. governments have the financial and technical means to do so. So unless you are some kind of political dissident, troublesome journalist, or other person of interest to a government entity, you are not a target.

By the way, no one at Apple has access to your password, period. That information is simply not available to anyone. It’s encrypted and stored on your device.

The bad guys want you to log on and remove your iPhone from the list of devices that are using your Apple ID because they have no way of doing this themselves.

If you do this, that will remove the Activation Lock on your phone, which will allow the bad guys to erase the phone......(they cannot get at your data on the phone, but they can erase the phone). This will allow them to set up the phone and sell it as a used phone.

Do NOT remove your iPhone from the list of devices that are using your Apple ID. You may receiving more threatening messages. Ignore and delete them.

True, you will never see the phone again, but you can really frustrate the bad guys who have your phone because it will be useless to them. If you can actually still locate your phone using Find My, it may likely be at a huge plant in Shenzhen that will take the iPhone apart and sell the parts or use them to try to remanufacture phones.

I'm not sure we can tell you how they got your number. Clearly, they found a way to uncover the number on your phone, but they still can't access the phone or its data as long as you had a passcode and the phone had Find My enabled before it was stolen, which it appears you did.