since now the content has no padding on mobile
In this post, you have set 2 container widths, 1 is full width which removes the theme paddings, and the other is 1100px by using a layout element.
If you want to keep the theme default padding, do NOT set the container width to full width.
You can check 2 places, if any of them are set to full width, switch it to default.
1. In the post editor > layout metabox:
https://docs.generatepress.com/article/layout-metabox-overview/#where-is-it
2. In the layout element > content at appearance > elements.
Let me know!