otomatic - 2020-03-24

This is not a bug, but a reading error on your part.
At the end of the installation it says to read the wamp(64)/mariadb_mysql.txt file, which you did not do.
This is repeated in right-click -> Help -> MySQL - MariaDB
So, read!
It is not difficult to understand that with two database managers active simultaneously, each manager has to use a different port.
Full stop.