Add another phone number to iMessage on MacBook
I've recently got a French SIM card while I'm on my year abroad in France, which is now active on my iPhone. When my mac asked me if I wanted to sync up this number to my iMessage on my computer, I accidentally pressed no, and I can't find a way of linking them up again....this means I'm no longer receiving any messages on my computer and it's super annoying. My FaceTime on my mac however IS linked up to this phone number!!
My preferences say I can be reached at my email address, but only give me an option to add another email address, not another phone number. Any ideas? Ideally I just need that original dialogue box to pop up again and ask if I want to link the phone number.
Thanks in advance!
MacBook Air (13-inch, Early 2015)