Talk to your PVP and they should link the cruises for you. I also go down to guest services and notify them that the cruises should be linked. You never know of a computer glitch. I also inform the cabin steward that I'm doing a B2B just so they don't haul away my luggage. If you have OBC left, go down to the casino and load it onto a slot machine, spin once then cash out. Go to the casino cashier and tell them you want to cash out. If you play in the casino, make sure to cash out the last night or you will loose all the money on your account. We did a B2B on the Dream and when they walked us back on the ship they took a picture of all of us and served us mimosas. If you like your table assignment on the first leg, take to the matried and ask for the same table assignment for the next cruise. If you have assigned dining.
Enjoy your B2B!!