Back End Developer for Mobile App

I am looking for a Back-end developer to complete a job that has been started but unfortunately was not delivered what I needed. It's the backend of a mobile app that we are trying to complete. Below are a few functionalities that I need to work. Must be able to complete these task and within a reasonable timeline. Must be able to do a booking function which creates a qr code order number etc when the booking is made, make the search page function and make all the buttons work in the profile edit section. Plus some other bits.