Passive Infrared Sensor stuck on HIGH value

Hi, I purchased a cheap PIR sensor on Aliexpress (https://www.aliexpress.com/snapshot/8152177236.html?orderId=78708513035190&productId=32519303005) and I was checking its digital output reading it from GPIO and with a LED wired on it.
The problem is that despite playing around with the sensitivity and delay screws, I see the digital output constantly HIGH, no matter how far or near the nearest object is.

Is there something I can try to be sure it's sensor's fault and not mine?

 

I can't see the pir sensor you bought, but normally a pir sensor measures movement so you have to be without movement to get it low. Or easier to put something on it so it has no sight.

Edit: typo

 

Wrap aluminium houshold foil around it, then turn it on, move it out of sight of any heat source.