@Nadine144 If both listings are for the same space, you will need to permanently remove one of them otherwise you'll go crazy keeping the calendars in sync with each other.
If the listings are for separate spaces you want to rent, i.e. separate private rooms, then you don't need to link the calendars since each would be rented separately.
Some hosts have private rooms and when they are not home, rent the entire house. In these cases it is essential to link the calendars because if a guest books the entire home, obviously the host can't rent the rooms as well.
Here are some links which may be helpful to you:
https://www.airbnb.com/help/article/476/how-do-i-snooze-or-deactivate-my-listing
https://www.airbnb.com/help/article/1864/how-do-i-link-airbnb-calendars-for-multiple-listings
Let me know if I have misunderstood your question!