Port 3001 affects MySQL Service

Hi. I have added port 3001 to TCP_OUT in CSF configuration because I need to connect an external API, but I notice that the change affects the MySQL service and the load up to 4000% in the WHM process manager. When I remove the port 3001 from the TCP_OUT configuration, everything was back to normal. Do you know what could cause that problem? Maybe I need to configure something else, idk.