We certainly can not diagnose you one line without and exam.
In fact, this type of symptom has multiple causes in addition to infection.
Acid reflux is one of the most common, and it seems that your doctors have not even considered this.
This is not likely to be a B12 deficiency, and you should be tested first for B12 and other B vitamins, before you supplement, in considering this cause.
Other causes are:
over stimulation from brushing, use of mouthwash
B vitamin deficiencies including B1,2,3,5,6,12 and folate
GERD...or reflux disease...yes even without heartburn
thyroid disease or diabetes
medications especially certain BP meds called ACE inhibitors
See an internal medicine doctor with this list and do not engage in self treatment until you have testing.
I am a double board certified US doctor.
Find me as needed. I am here daily by request in medical.
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