VKontakte leaks personal data to service departments?

Question

Personal Information

I made an order in the online store, where I indicated my name and phone number. Further, instead of a call from the courier service, I received a personal message in VK from a certain SDEK - Delivery. The profile is private, the phone was initially hidden from info. Question: what technologies do courier services use to access personal information and search for customers through Social Networks? Or is it VK leaking confidential information, turning a blind eye to the fact that the profile is closed by privacy settings?

Answer 1

https://vk.me/products/notify/
Functionality made specifically for business.
The function can be disabled in the settings in the privacy section.

Answer 2

There is a way to get your VKontakte id using clickdeking
Here I googled on a quick poke