What Could Be Causing My Child To Excessively Swallow And Burp, Especially At Night?

My 7 year old has been excessively swallowing. It s much worse at night around bedtime. She also burps quite a bit. We have cut out lactose and have given her pepto children s tablets but nothing seems to help. She also says it doesn t hurt her throat doesn t hurt and she doesn t know why she swallows so much. And we ve tried smaller bites, making sure mouths closed when chewing. Just at a loss and want her to not be so uncormfortable