After upgrade to 12.2.6, a value set IGR_SRS_YN is not working. It gives an error "FDFGVD failed due to ORA_00942 - Table or view does not exist". I found that IGS_LOOKUPS_VIEW is not available after upgrade to 12.2.6.
Shall I recreate this view or use an alternate view. Looks like this view is based on table igs_lookups_val.
You should not be messing around with seeded objects. If this object is no longer available in 12.2.6, then it would have been mentioned somewhere in the README or upgrade guide, along with instructions on what to do. Please open an SR with Support.