http://www.mayoclinic.org/diseases-conditions/airplane-ear/home/ovc-20200626
Usually self-care steps — such as yawning, swallowing or chewing gum —
can prevent or correct the differences in air pressure and improve
airplane ear symptoms. However, a severe case of airplane ear may need
to be treated by a doctor.
Since you/he has tried everything, a ENT would be a better source of diagnosis and advice that a RS forum.
Your doctor will likely be able to make a diagnosis based on questions
he or she asks and an examination of your ear with a lighted
instrument (otoscope). Signs of airplane ear might include a slight
outward or inward bulging of your eardrum. If your condition is more
severe, your doctor may see a tear in the eardrum or a pooling of
blood or other fluids behind your eardrum.
Medications
Your doctor may prescribe medications or direct you to take
over-the-counter medications to control conditions that may prevent
the eustachian tubes from functioning well. These drugs may include:
Decongestant nasal sprays Oral decongestants Oral antihistamines To
ease discomfort, you may want to take a nonsteroidal anti-inflammatory
drug, such as ibuprofen (Advil, Motrin IB, others) or naproxen sodium
(Aleve, others), or an analgesic pain reliever, such as acetaminophen
(Tylenol, others).
Self-care therapies
With your drug treatment, your doctor will instruct you to use a
self-care method called the Valsalva maneuver. To do this, you pinch
your nostrils shut, close your mouth and gently force air into the
back of your nose, as if you were blowing your nose. Once the
medications have improved the function of the eustachian tubes, use of
the Valsalva maneuver may force the tubes open.