1
general::
Phrase(s): goof on someone
Inf. to tease or kid someone. • I don’t believe you. I think you’re just goofing on me.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Make fun of, mock, as in He was always goofing on his little brother. [Slang; mid 1900s]
American Heritage Idioms