I can't understand why, when I open some pages with Sp Page Builder, they work correctly, while other pages return the following error message:

'Internal Server Error The server encountered an internal error or misconfiguration and was unable to complete your request. Please contact the server administrator to inform them of the time the error occurred and of any actions you may have taken that could have caused the error. More information about this error may be available in the server error log.'

I also took a picture of the monitor: https://ibb.co/4jzxQ6w. What could I do to fix the problem?

Thank you.