how to fix? Update Unavailable with This Apple ID

This update is not available for this Apple ID either because it was bought by a different user or the item was refunded or cancelled.

Available updates have changed.

Click “Show Details” to see the available updates.

no information follows.

no idea how to bypass.

just want to keep up with latest security. 2018-0002010.1106

pertaining to mac pro 3,1 recently updated from snow leopard to el capitan.