Cloud formation nested stack issue

Hello all. I have a collection of nested stack. I added a arn role to the root stack without editing the stack template after that the stack stopped updating each time I tried to update it rollback my update (error nested stack rollback the update) So I deleted the role to solve this issue, but I found that when I update the stack the deleted role is still appearing on the role option list, so I tried to press remove for this role because I don't want to use it in my update anymore and it didn't apply my updates when I press submit to finish update because it gives me error the role you selected not found I created a new role with the same name again to solve this issue and now I can submit my update but after the submissions it rollback my updates by nested stack so I'm facing the first issue again (nested stacks rollbacks my updates) what should I do? should I edit the template? and If yes should I add the arn role to resources or parameters? any advices please