Set upper flutter sdk version as 3.8.0-0.0.pre. This version of Flutter introduces a new API for WidgetsBinding which is not compatible with this version of the monarch package.
The monarch package version 3.0.x will support flutter versions prior to 3.8.0-0.0.pre.
The monarch package version 3.3 and above will support flutter sdk versions greater than or equal to 3.8.0-0.0.pre.