Cannot update an entity

Hi, i syncronized the tablet and appear the next msg in the log:

[20060925 07:31:16:612] E [MI/Smartsync ] Error while Smart Sync inbound processing: Error while Smart Sync inbound processing: com.sap.ip.me.spi.persist.IPersistenceException: Cannot update as no entity exists for IClassDescriptor/Key: cY01_ORD_TR_020/0010868091. Reset Smart Sync data on device to ensure consitency with middleware.

.....

This order doesn't appear in the GET_LIST BAPI of the SYNCBO, with what it would have to delete of the Tablet. But the orden is in IN_SYNC state and doesn't disappear.

Thanks.