Had this same issue rn uploading a model. Been doing avis for a few years now, checked the correct capitalization, made sure the names were the same in the Animator and parameters. Checked it all, same parameter type, same spelling, same name. Works in Gesture Emulator. What fixed it? Relaunching Unity. Guessing theres just a bug lately. Leaving this comment here for anyone else who was banging their head over a non-user issue.