Hi Chetan,
Apart from the regular checks for the access to _SYS_REPO on the schema which contains data tables and all, please check if your Attribute view entry exists in "_SYS_REPO"."ACTIVE_OBJECT". You can fire a query against "_SYS_REPO"."ACTIVE_OBJECT" where object_name = 'your_attribute_name'
It will confirm if you have active version of the object created successfully.
Regards,
Ravi