Hi,
There are early limosine buses from Tokyo City Air terminal ( T-CAT) to Narita ( 0545 and 0600) that get in at or before 7am
https://www.limousinebus.co.jp/en/ar..._tokyo/for/10/
You would probably need a taxi from your hotel to the air terminal ( have not used the T-CAT stop myself)
Regards
TBS