Blurry vision in left eye.eye doctor says it's eye strain but it's really bad when i first wake up.comes and goes all day randomly.what could it be?

Blurry vision DES: Blurry vision can be due to: dry eyes (most common) {from a variety of causes, mgd, blepharitis}, need for new glasses (refractive error;induced myopia); diabetes, headaches/ migraines; conjunctivalchalasis; rare issues (increased intracranial pressure/ papilledema, etc. Be sure you went to eyeMD, had full dilated exam, HVF, OCT, pupil check. If all normal, glucose check.