I am in need of Xamarin Developer who can fix small issues within 5 hours

I already have developed Xamarin Project Like This: User need to be able to get the profile if you are already registered. Firebase ID need to be updated. We have seen that if the app is uninstalled and then reinstalled the profile data is already there, but the notification ID have change and we are no longer able to send notification to the device. When a user click a notification it will disappear and the app will open, we would like for the app to open and show the notification in a dialog. We are also confused about the icon sizes, it looks like all icon are the same size, which make the to small on some screens and to big on other screens. That's all . I will provide source code to best appliciant Please apply ..