HDMI from PC to Samsung 32 HDTV and HDTV won't open apps from taskbar

Apr 11, 2018
I connect my PC to my 32 Samsung SMART HDTV via HDMI cable. Screen on TV won't fit, is bigger resolution than PC. When I click on an app from the TV taskbar, it won't open; the PC side works fine. This was all working fine last week. Nothing that I know has changed. Cable?