Diagnosis
The infrared (IR) sensor on the TV might be obstructed, or the remote's batteries are weak. The IR signal is a line-of-sight beam and needs a clear path.
How to Fix It
First, replace the batteries in the remote. Don't just check them—put in brand new ones. Weak batteries send a weak IR signal. Next, check the IR receiver window on the TV. It's usually a small, dark plastic piece on the bottom bezel. Wipe it clean with a dry cloth. Dust or smudges can block the signal. Make sure there's nothing directly in front of it, like a soundbar or decorative object.
If That Didn't Work
There might be interference from other IR sources, like bright sunlight, LED light bulbs, or a fireplace. Try turning off other lights in the room or closing the blinds to see if the remote responsiveness improves.
Heads Up
If you've lost the remote, you can use the 'Toshiba TV Remote' app on your smartphone as a temporary fix. The app connects over WiFi, so it doesn't need line-of-sight.