From the APA Style website:

"Works that cannot be recovered by readers are cited in the text as personal communications. Personal communications include emails, text messages, online chats or direct messages, personal interviews, telephone conversations, live speeches, unrecorded classroom lectures, memos, letters, messages from nonarchived discussion groups or online bulletin boards, and so on."

When using information from another source you must give credit to the original author or you are plagiarizing. You give credit by citing the source. Make sure your citation contains everything you would need to backtrack and find the information again. It is best to pick one citation style and be consistent.