Not able to see Sequences in any of the schemas

I am not able to see sequences in any of the schemas. I am able to see only Column Views, Procedures, Tables and Views

I am using Version: 1.0.52

Can anyone help how will i be able to see them?

I have Modeling and Public Roles granted to me

This happened after i was granted SELECT SQL privilege on _SYS_REPO and now even User System is also not able to remove this privilege.

What can be done to remove this privilege?