Hi, they probably won't because that card is not supported by AMD anymore. Feel free to add details here and one of us in the forums can try to help.
A few things to try, make sure the card is fully seated, try a different cable, a different display see if the DVI or VGA port works. Use DDU to uninstall the drivers and reinstall the Radeon driver that came with it. These newer drivers probably won't work. I have an R7240 in another PC and it uses a Radeon driver older than 2020.
Those are issues that are most common given no info other than what you're describing so far. I know they still sell these on Newegg but it's "end of life" product with basically no direct support or warranty via AMD.
"It worked before you broke it!"