That is strange.
Like Phantasico, I run Facer on a variety of both newer and older watches (Gear S2, Gear S3, Galaxy Watch, TicWatch2, Huawei Watch1, LG Urbane 2nd Edition) and Facer seems to run well on all of those (some paired to iPhone and others to Android.)
One question... is your Galaxy Watch a standalone or cellular model? The cellular models may run a different Tizen version based upon the cellular provider. I previously had two Verizon watches and was frustrated at their hit and miss support and delays in providing updates from the OS. Grasping at straws unless someone else has another idea... possibly even consider replacing the watch if still possible. If cellular, try turning off the cellular service (although this wouldn't resolve any software update issues.)
FYI... Samsung sent out a new watch update earlier this week.
Tizen is still 126.96.36.199, but the version is more important than the Tizen version. The software version is R800XXU1BSA4 on my standalone watch. Cellular models would have a different version.