Is this a bug in server?

[II./JG1_Krupinski]

Started getting this message today. Can't tell when it started as it's filled the console window with repeats completely. It still reports this error every 30-60 seconds.

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System.Exception: Network: Put Guaranteed message referenced to NOT mirrored object [NIJrnkNKJHiGX0uWBQV.1aV737N7piMxkBM
jjZK+8pW9Lm6Gwr3YNBDkiNC] -> [olIxYCog3p11yNow2Ap.wtZHQHobVPmqqXT5D5y+nUYgiLoxbq 4V1DLsVI0] (21).
at nj9eaRIaB7lQPjHstDe.4niqsmIVKFlqyjtWDYQ.OvTpT5TEfP J(wmdsRToiLvuBJdSMEcq , Int32 , Boolean )
at nj9eaRIaB7lQPjHstDe.4niqsmIVKFlqyjtWDYQ.lkLvN7PR7A H(wmdsRToiLvuBJdSMEcq , Boolean )
at 7uVsgGGRMQ1vm7up5IS.eIqU8XGETeyfQgpLViK.rYOVK6KHmD (4niqsmIVKFlqyjtWDYQ , wmdsRToiLvuBJdSMEcq )
at NIJrnkNKJHiGX0uWBQV.1aV737N7piMxkBMjjZK.replicateS tep(waU3CSYjdXUFeiQpaF , 4niqsmIVKFlqyjtWDYQ )
at uyLwyyouvVsG0tiA58a.HlYrNqoAQ2wFjRr91pb.1Ci2hrloij QmZlTjyXF(Object , waU3CSYjdXUFeiQpaF , Object )
at uyLwyyouvVsG0tiA58a.HlYrNqoAQ2wFjRr91pb.E3c2QFbfdI (4niqsmIVKFlqyjtWDYQ , Boolean )
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