diff --git a/src/block-management/block-manager.js b/src/block-management/block-manager.js
index 1158e7b3a64640..cf2bf53b8425ef 100644
--- a/src/block-management/block-manager.js
+++ b/src/block-management/block-manager.js
@@ -117,6 +117,7 @@ export default class BlockManager extends React.Component<PropsType, StateType>
 		const dataSource = this.state.dataSource;
 		const block = dataSource.get( index );
 		block.attributes = attributes;
+		dataSource.set( index, block );
 		// Update Redux store
 		this.props.onChange( clientId, attributes );
 	}