I have set alerts for Disk usage and now I want set alerts for Memory usage but I am not able to set it is giving error `FAILED TO TEST RULE`. Axes B is used and Axes C is Total.

[![enter image description here](https://i.stack.imgur.com/6Xfju.png)](https://i.stack.imgur.com/6Xfju.png)

[![enter image description here](https://i.stack.imgur.com/3O2B2.png)](https://i.stack.imgur.com/3O2B2.png)