If your present Eye MDs are unable or unwilling to give you an explanation of your problem you need a highly qualified Eye MD for a second opinion.
Common causes uncorrected refractive error, IOL out of position, macular edema, macular pathology, optic nerve or retina pathology, pre-existing amblyopia.
You can ask your Eye MD for a second opinion if you are comfortable doing so. You can look on www.aao.org for one near you. You would need a general Eye MD or a retina or neuro-ophthalmologist.
Keep looking, these types of things need answers.
JCH III MD