Need help aligning a custom region to the left on the Instance page

I added a new region to the Instance page, but it is aligning to the right. I need it to align to the left, similar to the existing Phone Number region.

The Phone Number region uses the “Default Single Column” item style, but this style is no longer available in the item style dropdown for new components. We are currently using the Message Component Layout, and I have tried styles such as Static Styled Text and Message Styled Text, but neither gives the expected left‑aligned layout.

Has anyone encountered this issue or knows how to replicate the original “Default Single Column” style or achieve the same left alignment with the new layout options?