SMS Security codes from Charles Schwab

There have been a number of threads here regarding xfinity blocking the sms security codes from Schwab after a switch from AT&T over to xfinity.  My wife and I recently made the switch from AT&T to xfinity and neither iphone 11 could not receive the SMS codes from Schwab.  We called xfinity and told them the problem.  xfinity was able to fix the problem on my wife's phone so she gets the sms codes from Schwab; however, the other phone cannot receive the codes.  It seems that someone at xfinity knows how to fix the issue, but it is not widely known.  Has anyone else been able to get sms codes from Schwab?