Invoice line amount is not auto updating in invoice distribution

When we make changes in invoice line after it's validation, invoice distribution line is not auto updating, we have to manually make changes in invoice distribution line as well, however system should automatically make changes in invoice distribution line if we make any changes in invoice line.
Ie. In one invoice, earlier invoice line amount was RS 1000 and after we have changes it to RS 1180, however in invoice distribution line it is still showing RS 1000 only, it didn't auto update and therefore after validating it goes into system hold because of invoice and line amount mismatch.