Help on Granting roles to the current user

Hello experts,

I am having trouble granting the user-created roles to my current user. I tried granting the roles using sql console as per the Open SAP training by Thomas Jung. But it throws following error

I also tried to grant the role to my current user by going to the user, double clicking it and tried to grant the role from there but there again it threw unknown error.

Please help.

Thank you,

Sumin