Hello and hope you are doing well.
There are tubes called 'Eustachian tubes' which connect the middle ear to the throat, this balances the air pressure in the ears. This tube can get blocked due to infections of the throat, which can give lead to a feeling of fullness in the ears. This can also result in infection of the ears. The blocked ears can be opened up by the valsalva maneuver, where air is blown into the cheeks against a closed nostrils, this sometimes helps to open up the tubes. Steam inhalations and warm salt water gargles can help clear the tube. Treating the throat infection should help clear the tubes. Please discuss this with your doctor am sure he will provide further assistance.
Hope this helped and do keep us posted.
It may be ETD, Eustachian Tube Dysfunction. Research it, but there's not much treatment beyond what Londres recommends.
Have you seen an ENT Specialist or an ENT/Allergist Specialist?
Have you tried an antihistamine in combination with a decongestant?