You don't need to put interviews you conduct, or other personal communications (email, chat, text message) on your References page. You only need to include an in-text citation in the body of your paper.
Use this format for the in-text citation:
(B. Mars, personal communication, June 10, 2019).
If you are citing a published interview, cite it on your References page according to where you found it (magazine, article in a database, web page, etc.).