Import from CSV formatting issue

I have two lists of data here: dm and dmHalo (see attached image). Theses are the same lists, the only difference is that dm was exported to a csv file and then reimported, while dmHalo was generated in the notebook session.

When I go to run an interpolation on the data set the interpolation does not recognize the csv imported data, as seen in the error message. I assume this is due to a change in formatting, but I am at a loss at how to revert to the native format.

Does anyone have an idea of how to do this?

Thanks you for your help!

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