We see an issue with OBS unit XOG. It's failing with the error Unique constraint violated PRJ_OBS_UNITS_FLAT_U1.
This is caused due to a mismatch between the max(id) of the PRJ_OBS_UNITS_FLAT table and the Next value obtained from PRCOUNTER
Release : 15.8.1
Component : CA PPM XML OPEN GATEWAY (XOG)
select max(id) from prj_obs_units_flat;
select prlastid from prcounter where prname='PRJ_OBS_UNITS_FLAT';
Reach out to support to help in fixing this.