When deleting files an error occured
org.caosdb.server.database.exceptions.TransactionException: org.caosdb.server.CaosDBException: could not unlink /opt/caosdb/mnt/caosroot/cloudkite-proc/processed_data/eurec4a/msm89/cloudkite/level_1/EUREC4A_CloudKite_MPCK-plus_MPCKplusBox-Dragonfly_Level-1_Flight009-20200209_v1.0 (copy).nc
It seems to be related to the file name. Other files could be deleted.