Clearly, you do not want your ear plugged up with wax.
But this is not the problem (nor is it normally when you have ear problems while scuba diving). It is the eustachian tube (connecting the middle ear to the pharynx). This is not accessible from the ear unless you ear drum is ruptured.

If the eustachian tube is closed and remains closed you cannot equalize the pressure and there is the problem. You are on decongestants and you are doing the equalization tricks swallowing, wiggling your chin and holding your nose and mouth closed and buld up pressure (i.e. exhale). If none of that works then it might be time to go for the tube solution mentioned above.... although it is pretty late in the game for this. I assume that it is not a big procedure, some HBO centers require this for all patients.

Best

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