Why is my MacBook Pro beeping after replacing the battery?

I just replaced the battery in my MacBook Pro 15" Unibody Mid 2012 with the one from ifixit. I have tried plugging in the laptop to charge and calibrate the battery but the laptop is now making a 3-beeping sound that does not stop. The orange indicator on the cable suggests the battery may be charging, but I am wondering how to solve this new beeping noise (has never happened before). Other things I have read suggest maybe it has to the with the RAM but I'm not sure. Thank you in advance to anyone for your help!