iPad Pro shuts down due to “low battery” 10-20 seconds after unlock

My iPad is at about 40%, and yet after about 10-20 seconds after unlocking it, it shuts down, and displays that it’s at low battery. If I try to power it on again, it doesn’t display the visual anymore, powers back on as usual, and then returns to a 30-50% range before shutting off again. Strangely, this only occurs while unlocked, and if it is on the lock screen or not displaying, it does not have the same problem.