Oracle Error Codes

must update the LOB only through the LOB buffers

LOB buffering is enabled for this LOB and there are buffers for this LOB in the buffer pool. Thus, updating the LOB through means other than the LOB buffers is not allowed.

How to Solve :

Update the LOB through the LOB buffers using the locator that has LOB buffering enabled. If this operation is required, buffers associated with this LOB should either be flushed as necessary or buffering should be disabled. Once this is done, reissue the command.