build failed ???

ERRORS:

Not enough information has been provided to MSBuild in order to establish a connection to a Remote Server. The project 'CompuChemApp.iOS' will continue building offline

CompuChemApp.iOS C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\MSBuild\Xamarin\iOS\Xamarin.Messaging.targets line 56

---------------------------------------------------------------------------------------------------------------------------------------------------------

Error Value cannot be null

Parameter name: key CompuChemApp C:\CompuChemApp\CompuChemApp\CompuChemApp\CompuChemXamlPage13.xaml line 1

My App is failing to build after adding the 15th xaml file with a big number of line coding in each of the xaml.cs files

Please help me solve these issue