@iampawan you have been caught plagiarizing several content from the web and have been banned accordingly.
Examples include:
https://steemit.com/utopian-io/@iampawan/flutter-building-a-whatsapp-clone-from-scratch
from this source: https://medium.com/@Nash_905/building-whatsapp-ui-with-flutter-io-and-dart-1bb1e83e7439
Another example includes:
https://steemit.com/utopian-io/@iampawan/flutter-backdrop-widget-material-design-2-0
from this source: https://medium.com/@CORDEA/implement-backdrop-with-flutter-73b4c61b1357

Any future contributions from you will be auto-rejected.