Expired Xfinity prepaid mastercard

Hi. Could an admin here help me?  I received a $200 prepaid mastercard as a promotion for joining Xfinity.  I intially tried to activate it when I got it and had nothing but trouble.  Tonight I spent an hour and got it display BUT now I see it expired and I called a number I found on Google and they said the terms and conditions are that they as a third party can't reactivate it because of the type of card it is but to reach out to XFinity and they could do it from their end.  I have not spent 1 cent of this card and would hate to lose $200 as this is a lot of money and I'm on a budget and it would really help me.  I have seen other responses to this same issue and the instructions are to send a message using an icon at top right to access messaging system but the only thing I see once logged in at top right is in app notifications bell and an icon to the right of it that just brings up my profile and such.  I am unable to find a way to sent this DM that admins in the past here have instructed folks to use to contact for help with this.  Please help.  Thanks