Chat asking for DOB, SSN and IMEI

This is not ok behavior, correct? My monthly bill for my internet jumped by $22.00 a month. I want to change plans because I was on a supposedly, "discounted plan". My chat person asked for my SSN, my DOB, and then my phone IMEI.

How can a company this big be asking its customers this information on a chat?

Is this legit when you reach an XFINITY chat and they ask for this?