[MultipleParadox]

The charging handle is metal and ends in a hook-shape. In the hook is a spring that gets screwed in the top of the receiver (above the hopup unit). This is the spring that let the charging handle get back to the closed position.

Then there's a plastic "L"-ish shaped piece that is screwed on the side of the charging handle, holding the spring in place, and this is the part that puts the bit of pressure on the dust cover to let it open when you pull the handle. This plastic part, breaks, all, the, time. (3rd time for me with light to moderate usage. very tired of that)

So yeah, this part broke, most likely. Airsoftparts.ca carry it