Obviously, the PIR is equipped with some kind of electronic switch, which impedes the very low current (34μA) flowing from pin SW to L to activate the input. Furthermore, the driving voltage for this tiny current is about 3V DC!
You may try the following:
(a) A small relay, contact NO and coil voltage 230V AC, coil be attached to L1 of PIR and Neutral. The contact of the relay goes to SW and L.
(b) Permuting L and N at the terminals of the PIR could be a remedy.
(c) Proposal (b) plus a very well isolated (!) resistor inserted in the connection between L1 and SW is another means to solve the issue. Wattage of the resistor may be 1/2 W or 1/4W, resistance 500kΩ to 1MΩ.