The following assertion was thrown while finalizing the widget tree:
Duplicate GlobalKey detected in widget tree.
The following GlobalKey was specified multiple times in the widget tree. This
will lead to parts of
the widget tree being truncated unexpectedly, because the second time a key is
seen, the previous
instance is moved to the new location. The key was:
- [LabeledGlobalKey<NavigatorState>#259af]
This was determined by noticing that after the widget with the above global key
was moved out of its
previous parent, that previous parent never updated during this frame, meaning
that it either did
not update at all or updated before the widget was moved, in either case
implying that it still
thinks that it should have a child with that global key.
The specific parent that did not update after having one or more children
forcibly removed due to
GlobalKey reparenting is:
- HeroControllerScope
A GlobalKey can only be specified on one widget at a time in the widget tree.

GoRoute(name: 'tos', path: '/tos', builder: (context, state) => TosP()),

And, it navigate to the page that I wanted. But, when I click the back button on a browser, it causes the problem. What can I do it? I designated the custom key but it doesn’t work as well.