I've been changing both GPS and VLOC (VOR, ILS) mode by VLOC or CDI button on GNS530. Even when I use GPS mode from the beginning, that issue happens, which is after activating Procedures on the ground, OBS showed off-flags (even when it showed no flags before activation). Activating them in the air, OBS shows off-flags sometimes but not always like on the ground. I've found that choose any airport first (this way, most of the time, OBS coupled with GPS). After verifying that then choose destination airport and procedure again so that OBS coupled with GPS. It seems like Working Title GNS 530 haven't been properly configured. I tried to uninstall it via Content manager, but there are 2 version of them. I was able to uninstall latest version, but I was unable to uninstall the other as the uninstall button was disabled. I just wanted to avoid uninstall and re-install MSFS2020 from the scratch for fixing that issue.
Thanks,