Chest Discomfort consistency between 2:00 and 3:00 a.m.

For 6 years I have been rudely awakened with pain below my sternum. I originally thought it was related to GERDS. I have been seen 2 gastroenterologist since that time and they do not have answers for me. I have had to Bravo tests done and the recent 2nd test in August 2021 says I have slight acid reflux. My doctor says it the #s were not high enough to diagnose my early morning chest pain to acid reflux. I have been to a cardiologist and did a stress test and my heart doc says the pain is not related to heart problems. One doctor thought there was a possibility of esophageal spasms and gave me a muscle relaxant (diazepam) for bedtime use. All this drug did is give me a dry mouth. I also had a pulse oximetry and it was normal.
I am at my wit's end on how to solve this problem. Most of the time I cannot fall back to sleep at these early wake up hours because of the discomfort. I do take Gaviscon when I am awakened by the pain and the seems to help but now sure why if it is not acid reflux. One gastro doc told me to take Hyoscyamine sulfate. This medication does not help me. Right now, I am thinking of seeing a psychiatrist as a last avenue. I would like to inquire why I wake up at the same time with this pain and maybe it is some form of brain chemical imbalance. I am willing to seek out all medical options. I will say that I am a trim and fit woman of 68. This condition is killing me for 5 hours of sleep is not serving me well emotionally and physically. If anyone can any ideas of what may be the culprit, I would appreciate any input. By the way, one doctor told me to go to Mayo in AZ for I had a mystery condition.