Could not update proposal due to duplicate user

[deepaksftc]

Noticed this error in logs during monitoring,

[2025-10-15T16:17:51.994+01:00] ERROR - Could not update proposal due to duplicate user

{"primaryKey":29184,"pi":1163463,"cois":[1086761,1087616,1163467,1163469,1162917,1163463],"duplicateUser":1163463,"level":"error","message":"Could not update proposal due to duplicate user","trace_id":"9b2c1a7e554c1d29544fc934a850e752","span_id":"8e80c6e50c5db055","trace_flags":"01","service_name":"proposal-backend","timestamp":"2025-10-15T16:17:51.994+01:00"}

From initial analysis, frontend doesn't seem to provide an option for adding duplicate user already. We need to find why and where this error is being thrown.

[ellen-wright]

Sprint planning notes: we will need to wait until the new CoProposer modal is in place as that might resolve this issue

[mutambaraf]

Maybe solved by : UserOfficeProject/user-office-core#1287

[ellen-wright]

Closing this, after checking the fix worked through the latest ISIS round