the library (@circlon/angular-tree-component) which declares TreeModel has not been processed correctly by ngcc, is not compatible with Angular Ivy

ERROR in node_modules/@circlon/angular-tree-component/lib/models/tree.model.d.ts:7:22 - error 

i am trying to use @circlon/angular-tree-component for the menu in tree-view with checkboxes. and throws error something like...

NG6002: Appears in the NgModule.imports of AppModule, but could not be resolved to an NgModule class.

This likely means that the library (@circlon/angular-tree-component) which declares TreeModel has not been processed correctly 
by ngcc, or is not compatible with Angular Ivy. Check if a newer version of the library is available, and update if so. Also consider checking with the library's authors to see if the library is expected to be compatible with Ivy.

7 export declare class TreeModel implements ITreeModel, OnDestroy {

how to resolve this...? thanx.