Shift+Alt+Cmd+R : For the internet reinstall but the problem still persists ; The solution for me was to restart the Mac just pushing Alt. In this case you will see this: Arriving at this point you need to select not your MacintoshHD but the one on the right instead which is the image of your Mac.

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Jun 01, 2020

Reinstalling Mac OS from the Recovery allows installing different versions of the operating system. Hence, before you start following the instructions, you have to make sure which version you want to reinstall. Reboot the computer and hold down one of the following key combinations in order to reinstall your preferred macOS version:

How to Reinstall Mac OS without Losing Data

How to reinstall macOS via Internet Recovery? The Mac operating system also includes various self-diagnosis and repair tools. Bear in mind, however, that these features might be susceptible to failure. When built-in tools or software-based solutions do not work, the last and most efficient solution is to reinstall the operating system. How to do a clean install of macOS Catalina | iMore