How do you spell “early”?
The words “earlier” and “early” not only have different meanings, but are also different parts of speech. Therefore, how to spell "early" and "earlier" is determined by completely different rules.
The word "early" is an adjective. In the adjectives, the number of letters “n” directly depends on with what suffix it was formed. If using the suffix "-n-", then doubling of the consonants will occur only when the base ends in "n". In this case, the word "early" is the basis of "wounds." When you add the suffix "-n-" and you get a doubling, so we write the adjective: early. Example: early morning.
The word “earlier” is an adverb, or rather, a form in a comparative degree, derived from the word “early,” so the number of letters “n” in it should be the same as in this word. The correct adverb: earlier.