Samsung s21 ultra 5g no security updates

Hello and thank you for taking the time to reach out to us here on our Xfinity Forums. I definitely understand wanting to make sure you have the most up-to-date software available to keep your devices protected.  Due to account security with Xfinity Mobile we don't have access to the Xfinity Mobile accounts. You would need to reach out to that department separately by calling or texting 1-888-936-4968 and one of our dedicated Xfinity Mobile specialists are there for assistance 24/7. You can also visit our Xfinity Mobile assistant page, where we have support available thorough chat as well: https://comca.st/3vkGv93. Have you already attempted to reach out to both of these options to contact an Xfinity Mobile representative?