The piezo system on my majesty guitar does not work

I got my Majesty 2 days ago and the piezo system isn’t working correctly. The magnetic pickups work perfectly but when I switch to the piezo I have to turn my amp up very loud and I get a faint clean sound that cuts in and out. Another problem I have is when I use the whammy bar the entire guitar cuts out and I have to unplug it for it to work again. I’ve replaced the batteries, and changed cables but nothing seems to work. How can I fix these issues???!!! I really want to test out the acoustic capabilities on this guitar.