SAP Message C$142 - Error in buffer: update failed (&1, &2)

Diagnosis
An error occurred when the system updated data stored in the buffer.

System Response
The system did not save the data.

Procedure
Notify your system administrator.
The table in which the error occurred is specified in parentheses. Youare also informed of the activity during which the error occurred.Here, the following letters have the following meanings:
I: Insert
U: Change
D: Delete