You must ensure that the Sink Flag Sinkable (tag 1780) option is set to Yes on the security master record in order to set up a sinking fund schedule in the Corporate Action table and the Schedule table.
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When you process corporate actions, Eagle Accounting does not process sinking fund payments or transaction information based on information in the schedule. During corporate action processing, the system creates the sinking fund payment transaction based on information about the sinking fund schedule in the Corporate Action table. Sink data should exist in both tables at all times.
For more information, see Understand Sinking Fund Bonds.