You got bad information from the AT&T rep. You can buy your watch from Apple, AT&T, or even BestBuy for example there is nothing special about buying only from an AT&T store other than a rep gets a commission.
The watch is designed to add a cellular plan right from the watch and should only take about 5 minutes to complete. You can set it up while you are preforming the initial watch setup are at any time later. The only possible catch is that not all AT&T plans support adding a "wearable" device. Here are the currently supported plans that allow you to complete the setup / activation directly from your Apple Watch Series 3/4/5.
A "wearable" plan is a specific type of line that has a unique phone number assigned, it is designed to share an unlimited data plan with other devices, that's why the limited number of supported plans as listed below.
Plans that directly support adding wearable plans:
The Apple Watch (GPS + Cellular) uses an eSIM that is populated OTA and replaces the need to get a physical NANO-SIM. If an carrier rep wants to send you a new SIM for your watch, just say thanks and try a different customer service rep.
- AT&T Unlimited & More
- AT&T Unlimited & More Premium
- AT&T Mobile Share Flex (various versions)
Dave
Yeah, I have no idea...Every time I went through the cellular setup, AT&T's website would error out, and tell me it had to be reviewed by an AT&T rep. I spent a couple of hours searching and trying various things, and nothing worked, including unpairing and repairing and starting over from scratch. Keep in mind, this was my first cellular version so I wasn't moving a plan from an earlier watch. Not sure that matters but it's working now so that's all I can say...lol
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