Tomcat doesn't work when it is started as Windows Service

I have installed Tomcat9 on a Windows server, and it has been installed as a Windows service. I have changed the listening port to 80 in server.xml. The Tomcat service works well when I use startup.bat or catalina.bat and I can access localhost.

However, if I start the Tomcat service as Windows service with Tomcat9w.exe or in the Service Windows app. I am not able to access the localhost homepage. I have checked the logs and a NullPointerException was shown in the localhost.log. How do I fix that? Thanks