please help

Ive purchased three different, models, a butterfly, a lightsaber, and an alchemy set, example: the butterfly comes with three files , i downloaded them, but when I went to open them in Chitubox, the second file read , THE SUFFIX ZTZ IS NOT SUPPORTED< ASK VENDOR FOR A RELEVANT SUFFIX PLUGIN, the others that I tried to download have files in them that give me this same reading, What do I do, I havent been able to even print one thing on this new Resin 3d printer, because of thies file problem , Can anyone help me , Thank you so much!