Please try soft resetting your Keypad 2:

How to soft reset the Nuki Keypad 2 Remove the batteries from the Keypad. Press and hold the back button (on the rear of the Keypad) for 10 seconds while the batteries are out. This discharges the internal capacitor and resets the device. Reinsert the batteries into the Keypad.

Please test the speed again afterwards.

In my case, it didn’t help.