What to do if everything seeing double but only in the middle.why?

If you have double: vision with both eyes open, binocular diplopia, see an ophthalmologist soon. In infants & kids,eye muscle weakness(es) can cause the eyes not to converge on the same target, with or without other disorders. Adult-onset diplopia can be from a variety of systemic illnesses, medications, corneal irregularities, very dry eyes or prior eye surgery. See your primary physician for this problem also.