The Format required for the Self Sign in with SMS recently changed and guests can no longer use the autofill on their device to enter the phone number or they will get a format error message. The captive portal gives no information on the proper format and the only documentation I know of for the proper format is page 660 of the R1 guide. There is no way that a guest will locate and read 660 pages to figure out the correct format to enter their ohone number.
