Baby Waylon and family

Since birth, my fiancé and I have had difficulty with our son Waylon thriving. Last Sunday his heart rate dropped into the 50s. Now he’s showing he’s stabilized but he’s not gaining weight and we are trying to fissure out why. He had to have a hernia surgery the beginning of October. This is the 3rd time he’s been omitted into the hospital. We hope we can figure out what’s wrong. So far we haven’t been givin any real answers to the problem. Any help is highly appreciated. Thank you for your time