Excel loses model all the time

[martingaleh]

In case you can't see the pict: https://snag.gy/v2MF7Y.jpg

I get this randomly all the time. sometimes I close excel and open it and its fine. Othertimes, its temporarily fine, but really brittle. When it breaks, I have to unload and reload the model and then all of my cubevalue functions will work again.
I think it may have to do with the fact I use the power pivot utilities to make the power pivot wihtout clicking the green logo and making the power pivot in a second and annoying step. Is there a way to fix this?