Inspect the duckbill valve and diaphragm for any damage — cracks, chips, holes, or tears. If damage is found, discontinue use immediately and replace the affected part.

Confirm the 4 main components (duckbill valve, diaphragm, container, and flange tunnel) are correctly assembled and fully sealed. Possible improper assembly points:

The duckbill is not fully pushed into position.

The container back is not fully seated under all four check marks.

The diaphragm rim is not fully seated along the groove edge.

The diaphragm lid is not firmly pressed and does not sit below the alignment mark in the groove.

The container is not fully clicked onto the hub.

The flange is not fully pushed in and securely clicked.

Adjust the fit: ensure your nipple is centered in the flange tunnel and the pump is sealed snugly against your breast.

Try a different insert size for a better fit.

Note: It takes time for your body to respond to a new pump — don't be discouraged if output is low at first.

If you have any other questions, please don't hesitate to contact eufy Support Engineers for further assistance.