Andy_B thank you for your reply, these are very helpful suggestions.
I did reboot the modem/router. Also contacted AT&T technical assistance, and they walked me through setting up 2gigahertz as well as guest access. So as it stands, I now have 3 Wi-Fi access addresses. All home devices are able to seamlessly use all there, except the S50. Please note, i’ve checked and verified.
1 There is no firewall.
2 Wi-Fi password has been entered correctly and tested for all three Wi-Fi addresses.
3 And have reset the S50
Thank you all, and please my friends, any additional suggestions would be gratefully appreciated.