Check all connections. Check that the transparent cap is firmly connected to all three connection points on the connector between breastshield and bottle. Hold the breastshield, not the connector or bottle, while expressing. Ensure the breastshield forms a complete seal around the breast. During single pumping, insert the unused tubing into the tubing holder. Do not kink the tubing. There should be no water in the tubing. All components must be completely dry.