firmware and odin help on my l720t topic

well i did a update with odin to get root back cuz i lost it due to knox and it said firmware upgrade encountered an issue. now it wont let me boot up the when i download the stock l720t firmware from sammobile odin wont get passed the write part with out saying Complete(Write) operation failed. what am i supposed to do now? ive used 3 diffrent odins and reinstalled my drivers. i just dont know plz help..
also it says odin mode write protect enabled and bust mode enabled