Gemini remote not controlling on/off of Samsung TV.

Gemini remote controls the Direct TV control box just fine. On/off to the control box no problem, channel selection no problem. Gemini also controls TV volume.

Gemini will not control the on/off of my Samsung TV. Tried fixing this may times without success. Tried to enter the Samsung model number manually several times, but did not work. 

What am I doing wrong? Just want the Gemini remote to also control the on/off feature. Is there a code I can enter to fix? Need help.

As an aside, I have another Samsung Tv in my home connected to a local cable system and the Gemini controls the on/off feature just fine. This is really strange.

Thanks,   Tim