Hello and hope you are doing well.
Food getting regurgitated at night could be due to GERD. Gastroesophageal Reflux Disease (GERD) is caused due to reflux of acid from the stomach into the esophagus. It could also be due to disorders of the esophagus. Try lifestyle measures to combat this. Take frequent small meals. Eat dinner about two hours before sleeping. Elevate the head end of the bed. Keep a food diary and note down what aggravates your symptoms and avoid them. Ensure to maintain optimum weight by regular exercise. Avoid non steroidal anti inflammatory medications NSAID's, quit smoking, eliminate alcohol and reduce stress levels. These measures need to be practiced long term for results.
Hope this helped and do keep us posted.
There is a number things that can cause this.
Any physician's visit yet?