Affirmed. See Reilly v. Barrera, 620 So.2d 1116 (Fla. 5th DCA 1993); Breitbart v. Zaucha, 185 So.2d 496 (Fla. 3d DCA 1966) (penalty interest presumed to be limited to defaulted payments); cf. THFN Realty Co. v. Kirkman/Conroy Ltd., 546 So.2d 1158 (Fla. 5th DCA 1989) (where the language is clear and unambiguous, the mortgage provisions control the application of the default rate of interest).