Battery not compatible

See User Guide.

Battery not compatible screen

What has happened: The battery that you inserted into the pump is not compatible. The pump requires one new AA (1.5 V) battery. For best results, use a new AA lithium (FR6) battery. The pump also accepts an AA alkaline (LR6) or a fully charged AA NiMH (HR6) nickel-metal hydride rechargeable battery.

Next steps:

To clear the alarm, remove the incompatible battery
Insert a new AA battery