If you mean chunks of
hair missing from the ears, then that
too is indicative of an infestation, causing
hair loss and inflammation due to scratching.
There is also the possibility the ear problem was caused by diet, but a flea infestation is my first thought.
If you are using Bakers Complete DRY food, then please be aware dry food in particular sometimes causes allergies. Bakers Complete is also one of the worst dog foods there is, getting an alarming 0.1 out of 5 on AllAboutDogFood UK site.