In between should always appear as two words. Although inbetween is common, it is a misspelling and does not appear in any English dictionary. Unnecessarily adding in to between is also a common grammatical mistake. As a compound adjective, in-between should be hyphenated.

What is the difference between in between and between?

The word in between differentiates itself slightly from the word between as it describes all the things that lay from one thing, point, place or person to the other. In between is the word that shows the intermediate things lying between two things that may be either imaginary or real.

Do you put a hyphen between in person?

No, only if it's being used as an adjective in front of the noun it modifies, e.g.: "I did an in-person interview." But you're using it as an adverbial phrase modifying the verb "addressed," so no hyphen should be used.