Cannot read property 'data' of undefined

ArticlesComponent.html:13 ERROR TypeError: Cannot read property ‘data’ of undefined
at Object.eval [as updateDirectives] (ArticlesComponent.html:13)

I’m confused, it kind of works, I can see the articles but I am unable to see the live data once updated or added, I need to refresh the page?!

Please help

<tr *ngFor="let article of">
Isn’t it saying it doesn’t know what this is: “articles”
i.e. “articles” has no property data because there is no “articles”, it is undefined.

Articles is defined on line 18 of articles.component.ts

articles: Article[];

can anyone help here please?

can anyone help me here please?

Did you ever get this resolved? I am sorry, I did not see the follow up.