Door Latch Problem

2006 Doublecab Prerunner SR5 4.0 V6 Automatic trans (if it matters)

OK. Its not the "usual" door latch issue (from what I can find here on the forums). The handle works fine, the power actuator works fine, the door opens and closes from the inside and out just fine.

My problem is the actual latch that connects to the strike plate loop thing on the body that physically secures the door closed.

Sometimes, but its becoming more frequent, the part of the latch that actually rotates to hook around the striker plate thing will drop down on its own with no warning so that it wont let the door latch.

Its almost like there is maybe a spring or something inside the door latch that holds that piece up that is getting weak and on its way out?

Is there some DIY internal fix to the latch I can do to resolve it, like replace a spring or something, or should I just shell out the $150ish and just replace the entire latch assembly in the door (just the latch part, not all the actuator and stuff.)

I'm getting tired of wielding a screw driver to rotate the thing back up whilst holding the door opener handle (usually when its dark outside).

TIA