That means you didn't install the AMD Driver package correctly/wrong one or the AMD driver is corrupted when you installed it.
Follow these steps and see if it fixes your problem:
1- Download DDU: https://www.wagnardsoft.com/forums/viewtopic.php?t=3793
2-Download the latest AMD Driver for the RX580 from AMD Download page: https://www.amd.com/en/support/graphics/radeon-500-series/radeon-rx-500-series/radeon-rx-580
3-Delete the last AMD Driver Installation folder at C:\AMD that was created, if applicable.
4-Disconnect your Internet/Wifi to prevent Windows from installing a different driver while installing the new AMD Driver
5-Run DDU . When it finishes and boots back to Windows Desktop
6-Run the AMD Driver Package.
7-If successful, reconnect the Internet/WiFi and again delete C:\AMD installation folder.
After the AMD Driver installs run GPU-Z and upload a photo of it to see if all the APIs have been enabled and to check the Make & Model of your new GPU card and related data.
