Why were an SMS and email sent by CDSL informing about the blocking mechanism for payin of securities?

As per SEBI guidelines (WEB), depositories must validate the depository transfer instructions with the Clearing Corporation (CC) obligation details. An obligation is the shares that must be given to the CC for delivery against the sell orders executed. If the transfer and obligation details match, the transaction goes through. However, if the details do not match, the transfer is rejected.

Clients are not required to take any action because Zerodha ensures that the CC obligation details based on the Unique Client Code (UCC), Trading Member (TM) ID, Clearing Member (CM) ID, Exchange ID, ISIN, quantity, settlement details, etc. all match for the securities to be successfully transferred.