Aakash Institute — A employee trying to contact me personally

Yesterday I received two landline calls from Akash Institute, I was unable to pick up as I was away from the phone. Later someone called me by their personal number claiming to be and Employee of Akash Institute. He asked me if I am interested in CAT examination and I've filled certain forms and information about me relating to this examination on Akash's website which I certainly remember I didn't. Since he called me via his personal message now he is also texting me on my personal WhatsApp number. How can you call it a professionalism? Is this how you manage your employee to let them contact your customer personal and make them uncomfortable?

The person is from Lucknow Branch.
Namely, Sahil Jaiswal.
His mobile number- +91 [protected]