I forgot last night to examine my OHT, then seeing Rich’s reply, I did.
When you deploy your plier head, do so slowly and watch the releasing buttons. When the head is fully extended the the buttons should spring out, this locks the plier head open. You must fully dipress each button to retract the plier head.
I have observed that sometimes “flicking” the plier head out, it does seat fully to the end track and the side buttons do not lock.
Lubrication the plier track on rack side of the handle will allow for smoother operation.
But if those buttons do not spring out the plier head will remain out.
Also, examine inside the handles and make certain there is not debris preventing the pliers from fully extending.
If LM inspected, they likely tested by grasping the head pulling it out. Not flicking as many owners do, and not emulating your technique.
Hope this may provide you relief😉