Fix a Midi Issue in the code of a Arduino plugged through USB to computer

hi, I have a device that is like a midi controler using arduino and usb cable to computer. (to send musical notes to a daw software and act as a piano sequencer), (I use ableton live on osx). I am looking for someone with experience in arduino coding, this code has a midi function that is working fine except there is some kind of note off error or another error that causes notes to be played when not asked. I need someone who can fix this code error so I can make my device nice and functional. this should be a easy fix if you know midi and arduino code. I have a small budget because this is my first project but I will order more jobs from you if I like your work. I would like to pay 5-10 dollars for this.