Hello! Thank you for reaching out! If none of the troubleshooting was helping from the community I would recommend reaching out to our smart things community using the following link: https://community.smartthings.com
@userdgc3Zrimbq Welcome to the Samsung Member's Community. I'd be pleased to assist you with resolving the issue with your Samsung Smartview Issue.
1. On your Samsung Television 2. Press The "Settings Button" 3. Go the "General Tab" 4. Select Network 5. Select "Reset Network"
I've personally experienced this on my own Samsung Televison when my Samsung Galaxy Phone could not find my Samsung Television. Even after I've connected to it before. Any time that you encounter this issue. Just reset your Samsung Television Network Settngs. Then your phone should see your Samsung Television again.
Of course you will need to reconnect to your Wi-Fi or Ethernet. But this has worked for me multiple times! I hope that I was able to assist you with resolving your connectivity issue. Please select my answer. Then (the three dots ... in the corner of my answer). "Accepted Solution" Thank you for using the Samsung Member's Community. Thank you!
Okay I know your Samsung UN55RU7100FXZA has the Current Firmware Update. So we can eliminate that as a potential issue. On your Samsung Galaxy S21 what version of Samsung Smartview does your phone say?
