YValues in Dynamic Chart changing to =[0]!

I wonder if anyone has had this problem?

I've got a couple of dynamic charts that break every time I close and open the file. When I close, the YVales read "solar.xlsx!dynLoadVoltage" under the "Select Data Source" window.

When I reopen the file, they've changed to "=[0]!dynLoadVoltage" and they no longer update when the data changes.

I've attached the file for reference.
Any suggestions?

Thanks for reading!