Just wanted to post a PSA about how I fixed this problem on my Apple Watch SE.
Left the house last night to pick up dinner (without iPhone) knowing I had my Apple Watch w/cellular should I need a phone. When I went to send a text, my watch reported no internet. I checked my cellular settings and it said “No SIM”.
Tried restarting. Didn’t help. Did a shut down, then turn back on. Didn’t fix it. Once I got back home, I looked in my Apple Watch app on my iPhone, and under the Cellular section I tapped on Add a Plan (even though I already had a watch plan and confirmed it was active at AT&T). After a minute or two of it checking with AT&T, my cellular capabilities returned to my watch. Easy fix.
I wonder what causes the SIM to disappear in the first place?
