Lonzo Ball was pissed to be called a "deadbeat dad" by his ex-GF ... and when the Lakers star confronted her about the comment -- he told her, "It's really not funny."
Denise Garcia -- Zo's baby mama -- went on social media in October and was asked to "blink if Lonzo is a deadbeat dad" ... and she blinked with both eyes while laughing.
Cameras caught Lonzo confronting Denise over the post on the Ball family's Facebook reality TV show ... when he ripped into her for making the accusation.