My hdmi adapter is not working

So the first time I tried it it was completely fine but then a few months later I want to try it again and then it like completely stopped I connected to the HDMI adapter my phone and then I put the HDMI cable in and then I put the HDMI cable on the computer and it did nothing so I just wanted to see so I put my charger where it supposed to go on the HDMI adapter and after that I plugged in my charger to the to the thing in the world after that I have the TV told me like this cold so I scanned it with my camera tells me to drop cast or something in the Internet and I did it told me to download it so I download it after I downloaded it and told me to like updated version of something that showed on my TV which I did after I updated it nothing happened I don’t know what’s going on please help me.