I heard this yesterday on a radio show.

Problem:
The adverb does not match the tense of the verb.

Explanation:
The adverb “yet” means at the present time.

The expression “did not call” is in the past tense, so “yet” does not go with “did not call” (or any other expression in the past tense).

In other words, it makes no sense to say, “He did not call back at the present time.”

To fix this, one must change the expression to the present tense.

Solution:
“He has not called back yet.”