Yeah. So I’m not sure why it won’t show

Hey guys I have a problem I’m not understanding.
I’ve connected my rasp pi to my tv via hdmi cord and it worked perfectly fine once I got a charging block that had more power to support it. However I moved and am trying to connect my rasp pi to my tv screen and it won’t read for some reason. The tv and rasp pi both turn out however for some reason the hdmi won’t show on the tv. It was working before i left so not too sure what could’ve gone wrong Any thoughts on this ?

I wanted to ask a quick question as I’m new to this! I’m planning on building a smart mirror and using my old 32inch smart tv as the display. My question is, will the display show clearly through the mirror if I leave the casing around the tv as it usually is which would leave around a 3/4 inch gap between the display and mirror. or do i have to take apart the tv so I can have the display right up against the glass. I appreciate your guys input!