Can i stack some shield on your [ Smart Servo Shield for dynamixel ] ?

Hi ,
I just want to know if we can " stack " another shield on your [Smart Arduino Digital Servo Shield for Dynamixel AX ]

• https://www.dfrobot.com/product-958.html

Actually i have an arduino Uno with your [Smart Servo Shield for dynamixel ] stack on it. And i try to stack the [Arduino Motor Shield Rev3] on your [Smart Arduino Digital Servo Shield for Dynamixel AX ]

• https://store.arduino.cc/arduino-motor-shield-rev3

But when i do that, i don't know why . I lose energy...
I use a battery 14V for my Arduino Motor Shield Rev3 , but only 7~8 V arrive to my stepper motor when i drive it. And when i remove your [Smart Servo Shield for dynamixel ] , it's work fine

I will be happy to get answer about this. Many thanks in advance