Cannot find module ‘ngx-bootstrap’

Based on ngx-bootstrap documentation, angular 9 doesn’t support this kind of import . If you want to use BsModalService , ButtonsModule and so on you have to import them as below :

// RECOMMENDED
import { BsModalService, BsModalRef } from 'ngx-bootstrap/modal';
import { ButtonsModule } from 'ngx-bootstrap/buttons';

instead of :

// NOT RECOMMENDED
import { BsModalService, BsModalRef , ButtonsModule } from 'ngx-bootstrap';