Firefox keeps asking me for my master password.

Hello,

When I create a master password, I am prompted for the password every time I open Firefox.

There is a solution, but it doesn't work, this one:
https://support.mozilla.org/en-US/kb/firefox-stops-asking-master-password

I have tried several extensions, but none secure the passwords in the Firefox settings.

How can I fix this issue?

Thank you.

Configuration: Windows / Firefox 75.0