Use a micro-USB cable capable of data transfer (some cables are charge-only and will not work).
If the official link is temporarily unavailable, some users in the gaming community have archived versions (such as v1.5.010722) on sites like MediaFire via community threads on Reddit . Supported Devices hyperkin upgrade tool download
The primary source for all official Hyperkin firmware is the Bluetooth Controller Firmware Downloads page on the official Hyperkin Wholesale site. Use a micro-USB cable capable of data transfer