*Warning* Multiply Owned Objects followed by different number (i.e. "f77" for example) is showing that the dataset is corrupted. It means that multiple operations are trying to access the same objects at the same time. This handle ID is specified in the "Multiply Owned Objects " message. Use the following lisp to delete the object.
(entdel (handent "handleID"))
Replace handleID with the number given, but leave the quotes. Then paste it into the command line.
Andrew Ingram
Civil 3D x64 2019
Win 10 x64 Pro
Intel Xeon E5-1620
32 GB Ram