The best long term answer to this problem is to improve the quality of your stomach acid. As weird as it seems, the better the quality of the stomach acid, the tighter the “cap” or sphincter on top of the stomach closes. Tight cap = no acid sloshing back into your mouth. There’s many ways to improve the acidity of your stomach, including eating right (fewer processed foods, especially carbs), chewing your food well before swallowing, reducing stress and using natural aides like apple cider vinegar and bitters to stimulate the stomach acid. The fastest acting natural solution to acid reflux are Raft Forming Alginates. Here’s an article that can help you understand your options better.