How do I install a new firmware on a TV when I can't control it?

Hi,

My Toshiba 49L5650 TV is from Thailand, and I brought it to Bangladesh. So I used it for 4 days, and I don't know what happened, but when I turned it on, it started to glitch out. It turned on, displayed "Toshiba", as usual, then had a loading animation, which is usual, but it then shows a black screen. After 20 seconds, it will shut off, and within 1 second it'll turn back on. The TV Remote or Buttons don't work. The TV has a heart, but no brain essentially. Someone told me that the firmware may have been deleted or corrupted. How can I install a new firmware onto the TV, when I can't even control it with the remote?

Additionally: It would be nice if someone could help me find a firmware download for the model stated above