Here on my Windows 8 I just used Wiipair and then opened Dolphin and clicked "refresh" button, everything worked fine... Try to uninstall your BT driver and let Windows install it again. In last case (or if you have an RVL-CNT-01-TR wiimote) install the Toshiba bluetooth stack... Also, rememeber that at least for me, the default windows bluetooth stack works very well (better than the other stacks), so, I recomend trying the Toshiba stack only if you have the TR wiimote.
Avell A70 MOB: Core i7-11800H, GeForce RTX 3060, 16 GB DDR4-3200, Windows 11 (Insider Preview)
ASRock Z97M OC Formula: Pentium G3258, GeForce GT 440, 16 GB DDR3-1600, Windows 10 (22H2)
ASRock Z97M OC Formula: Pentium G3258, GeForce GT 440, 16 GB DDR3-1600, Windows 10 (22H2)