Value could not be determined statically - breaks build

[unrealxqt]

So when adding the line MatCarouselModule.forRoot() into the app module imports it produces a compile time error:

Value at position 7 in the NgModule.imports of AppModule is not a reference
Value could not be determined statically.(-991010)
app.module.ts(30, 5): Unable to evaluate this expression statically.
app.module.ts(30, 5): A value for 'forRoot' cannot be determined statically, as it is an external declaration.