Badari Beat-down bug

I have tried badari beat-down (egyptian level where you kill 4 chieftans and 10 gold caravans) countless times today. Each time i kill all 10 caravans and all 4 chieftans. The game registers that I complete the objective to kill the caravans, but it only registers that I kill one (the first)of the four chieftans. Please fix this!!!