Do you have any / many connectors? If not there is a way to recover from it. If you do have connectors, send me a PM about getting this fixed.
Sorry @bertabcd1234, didn't see your post.
With no connectors, it is possible to remove the Hub Variables settings-app, which should clear the error and make Hub Variables work again. Doing this is non-destructive of Hub Variables, but would create a problem with connectors (there is a fix for this, but subject would be PM).
To remove the Hub Variables setting app, you need to edit the URL on its page (even if throwing an error), from this:
To this, substituting your hubs' IP address and the appId number (25043 in screenshot).
Then, on the page that comes up, lower right, you can Remove Hub Variables. Once this is done, relaunch Hub Variables and it should be fine.
PM to me for how to deal with connectors should you have them.
