Won’t connect to cellular

Thank you. I will give them a call. We just switched from Verizon to AT&T but I bought my watch from the Apple Store. I was going to have them do all the setting up like we’ve done before but the guy that helped us said they don’t add lines (maybe just watches I can’t remember) for AT&T. I’m not sure if it’s just AT&T or not. Anyway, do you think they may could still help me with my issue? I called AT&T last night and the lady said since it was a new account I would have to wait several days to be able to connect it. Honestly it made no sense because I know when you sign up with them and purchase new devices, they don’t say, “well you will have to wait a few days before you can use them”. It’s so frustrating.