The ‘@email.uscc.net](mailto:’@email.uscc.net)’ to get it to work.
Also, a minor technicality - but the instructions show 2 different phone numbers (212 vs. 222). I doubt it would ever confuse someone - but thought I’d point it out.
For example, if you use T-Mobile and your mobile number is 212-555-1234, your address is 2225551234@tmomail.net.