Explanation

Step 1: Adjust the version number.
Step 2: Select the managed solution.
Managed Solution: A managed solution is a finalized solution that can be distributed and installed. They are created by exporting an unmanaged solution by setting restrictions to prevent any further customizations. The whole point of Managed is locking down the Component states so they cannot be edited. Deleting the Managed Solution will remove all its customisations as well as data contained. Managed Solutions become read only once deployed so they cannot be manipulated.
Step 3: Publish all changes.
Reference:
https://powerusers.microsoft.com/t5/Power-Apps-Pro-Dev-ISV/Managed-vs-Unmanaged/td-p/495685