Can't use performance_schema in my mysql server

I am using AWS RDS aurora mysql 5.7 serverless but in RDS I have enabled the performance_schema parameter, I have connected my RDS to mysql workbench version 6.3 in mysql workbench when I am checking the parameter performance_schema it is showing disabled and I have also checked performance_schema has no data in it. I want to check the unused indexes in the schema for that I have to use performance schema.