Im sorry for your trouble loading the galaxy store on your watch. One step you can do is force stop the app on the galaxy wearable app. To get to it is:
1: tap on the galaxy wearable app
2: tap on manage apps
3: tap on the galaxy store
(There isn't an option to interact with storage)
So you have to
4: force stop the app
I hope this helps.
I also wafacing the same issue. Can you please provide an urgent solution. I am samsung galaxy S3 frontier with OnePlus 7t.
I have also tried the above steps but they didn't work.