Angular-Formly Styles are not working after adding matexpansionpanel

Question

Here is the stackblitz for code

https://stackblitz.com/edit/angular-syo244?file=app%2Fapp.component.html

in app.component.html commented code for required output

Answer 1

https://stackblitz.com/edit/angular-syo244?file=app%2Fapp.component.html

with the help of formly team and please update the answer if there is any alternate.

https://github.com/formly-js/ngx-formly/issues/865