Diagnosing this issue can be complicated and often dependent on many variables that are unique to the wiring in your house.
If the problem persists, please try increasing the minimum brightness setting of the switch by following the steps on page 3 in the instruction manual.
If increasing the minimum brightness did not solve the problem, we suggest either increasing the load on the circuit by using higher power lamps, or by fitting an LED bypass over the first lamp in the circuit.